Merge branch 'py3' of https://github.com/eli-schwartz/calibre

recipes/sltrib.py

@@ -1,56 +0,0 @@
-from calibre.web.feeds.news import BasicNewsRecipe
-
-class AdvancedUserRecipe1278347258(BasicNewsRecipe):
-    title      = u'Salt Lake City Tribune'
-    __author__ = 'Charles Holbert'
-    oldest_article = 7
-    max_articles_per_feed = 100
-
-    description            = '''Utah's independent news source since 1871'''
-    publisher              = 'http://www.sltrib.com/'
-    category               = 'news, Utah, SLC'
-    language               = 'en'
-    encoding               = 'utf-8'
-    #delay                  = 1
-    #simultaneous_downloads = 1
-    remove_javascript      = True
-    use_embedded_content   = False
-    no_stylesheets         = True
-
-    #masthead_url = 'http://www.sltrib.com/csp/cms/sites/sltrib/assets/images/logo_main.png'
-    #cover_url = 'http://webmedia.newseum.org/newseum-multimedia/dfp/jpg9/lg/UT_SLT.jpg'
-
-    keep_only_tags = [dict(name='div',attrs={'id':'imageBox'})
-                      ,dict(name='div',attrs={'class':'headline'})
-                      ,dict(name='div',attrs={'class':'byline'})
-                      ,dict(name='p',attrs={'class':'TEXT_w_Indent'})]
-
-    feeds = [(u'SL Tribune Today', u'http://www.sltrib.com/csp/cms/sites/sltrib/RSS/rss.csp?cat=All'),
-           (u'Utah News', u'http://www.sltrib.com/csp/cms/sites/sltrib/RSS/rss.csp?cat=UtahNews'),
-           (u'Business News', u'http://www.sltrib.com/csp/cms/sites/sltrib/RSS/rss.csp?cat=Money'),
-           (u'Technology', u'http://www.sltrib.com/csp/cms/sites/sltrib/RSS/rss.csp?cat=Technology'),
-           (u'Most Popular', u'http://www.sltrib.com/csp/cms/sites/sltrib/RSS/rsspopular.csp'),
-           (u'Sports', u'http://www.sltrib.com/csp/cms/sites/sltrib/RSS/rss.csp?cat=Sports')]
-
-    extra_css = '''
-                .headline{font-family:Arial,Helvetica,sans-serif; font-size:xx-large; font-weight: bold; color:#0E5398;}
-                .byline{font-family:Arial,Helvetica,sans-serif; color:#333333; font-size:xx-small;}
-                .storytext{font-family:Arial,Helvetica,sans-serif; font-size:medium;}
-                '''
-
-    def print_version(self, url):
-        seg = url.split('/')
-        x = seg[5].split('-')
-        baseURL = 'http://www.sltrib.com/csp/cms/sites/sltrib/pages/printerfriendly.csp?id='
-        s = baseURL + x[0]
-        return s
-
-    def get_cover_url(self):
-        cover_url = None
-        href =  'http://www.newseum.org/todaysfrontpages/hr.asp?fpVname=UT_SLT&ref_pge=lst'
-        soup = self.index_to_soup(href)
-        div = soup.find('div',attrs={'class':'tfpLrgView_container'})
-        if div:
-            cover_url = div.img['src']
-        return cover_url
-

src/calibre/ebooks/__init__.py

@@ -67,7 +67,7 @@ class HTMLRenderer(object):
             buf = QBuffer(ba)
             buf.open(QBuffer.WriteOnly)
             image.save(buf, 'JPEG')
-            self.data = bytes(ba.data())
+            self.data = ba.data()
         except Exception as e:
             self.exception = e
             self.traceback = traceback.format_exc()

src/calibre/ebooks/pdf/render/serialize.py

@@ -464,7 +464,7 @@ class PDFStream(object):
         ba = QByteArray()
         buf = QBuffer(ba)
         image.save(buf, 'jpeg', 94)
-        data = bytes(ba.data())
+        data = ba.data()
 
         if has_alpha:
             soft_mask = self.write_image(tmask, w, h, 8)

src/calibre/gui2/__init__.py

@@ -1,6 +1,10 @@
+from __future__ import absolute_import, division, print_function, unicode_literals
+
 __license__   = 'GPL v3'
 __copyright__ = '2008, Kovid Goyal <kovid at kovidgoyal.net>'
+
 """ The GUI """
+
 import glob
 import os
 import signal
@@ -354,7 +358,7 @@ def is_widescreen():
     global _is_widescreen
     if _is_widescreen is None:
         try:
-            _is_widescreen = float(available_width())/available_height() > 1.4
+            _is_widescreen = available_width()/available_height() > 1.4
         except:
             _is_widescreen = False
     return _is_widescreen
@@ -687,7 +691,7 @@ def pixmap_to_data(pixmap, format='JPEG', quality=None):
     buf = QBuffer(ba)
     buf.open(QBuffer.WriteOnly)
     pixmap.save(buf, format, quality=quality)
-    return bytes(ba.data())
+    return ba.data()
 
 
 def decouple(prefix):
@@ -736,7 +740,7 @@ class Translator(QTranslator):
         try:
             src = unicode_type(args[1])
         except:
-            return u''
+            return ''
         t = _
         return t(src)
 
@@ -766,8 +770,8 @@ def load_builtin_fonts():
                 if fid > -1:
                     fam = QFontDatabase.applicationFontFamilies(fid)
                     fam = set(map(unicode_type, fam))
-                    if u'calibre Symbols' in fam:
+                    if 'calibre Symbols' in fam:
-                        _rating_font = u'calibre Symbols'
+                        _rating_font = 'calibre Symbols'
 
 
 def setup_gui_option_parser(parser):
@@ -881,7 +885,7 @@ class Application(QApplication):
         self.line_height = max(12, QFontMetrics(self.font()).lineSpacing())
 
         dl = QLocale(get_lang())
-        if unicode_type(dl.bcp47Name()) != u'C':
+        if unicode_type(dl.bcp47Name()) != 'C':
             QLocale.setDefault(dl)
         global gui_thread, qt_app
         gui_thread = QThread.currentThread()
@@ -903,7 +907,7 @@ class Application(QApplication):
                 'calibre versions newer than 2.0 do not run on Windows XP. This is'
                 ' because the graphics toolkit calibre uses (Qt 5) crashes a lot'
                 ' on Windows XP. We suggest you stay with <a href="%s">calibre 1.48</a>'
-                ' which works well on Windows XP.') % 'http://download.calibre-ebook.com/1.48.0/', show=True)
+                ' which works well on Windows XP.') % 'https://download.calibre-ebook.com/1.48.0/', show=True)
             raise SystemExit(1)
 
         if iswindows:
@@ -978,22 +982,22 @@ class Application(QApplication):
         icon_map = self.__icon_map_memory_ = {}
         pcache = {}
         for k, v in iteritems({
-            'DialogYesButton': u'ok.png',
+            'DialogYesButton': 'ok.png',
-            'DialogNoButton': u'window-close.png',
+            'DialogNoButton': 'window-close.png',
-            'DialogCloseButton': u'window-close.png',
+            'DialogCloseButton': 'window-close.png',
-            'DialogOkButton': u'ok.png',
+            'DialogOkButton': 'ok.png',
-            'DialogCancelButton': u'window-close.png',
+            'DialogCancelButton': 'window-close.png',
-            'DialogHelpButton': u'help.png',
+            'DialogHelpButton': 'help.png',
-            'DialogOpenButton': u'document_open.png',
+            'DialogOpenButton': 'document_open.png',
-            'DialogSaveButton': u'save.png',
+            'DialogSaveButton': 'save.png',
-            'DialogApplyButton': u'ok.png',
+            'DialogApplyButton': 'ok.png',
-            'DialogDiscardButton': u'trash.png',
+            'DialogDiscardButton': 'trash.png',
-            'MessageBoxInformation': u'dialog_information.png',
+            'MessageBoxInformation': 'dialog_information.png',
-            'MessageBoxWarning': u'dialog_warning.png',
+            'MessageBoxWarning': 'dialog_warning.png',
-            'MessageBoxCritical': u'dialog_error.png',
+            'MessageBoxCritical': 'dialog_error.png',
-            'MessageBoxQuestion': u'dialog_question.png',
+            'MessageBoxQuestion': 'dialog_question.png',
-            'BrowserReload': u'view-refresh.png',
+            'BrowserReload': 'view-refresh.png',
-            'LineEditClearButton': u'clear_left.png',
+            'LineEditClearButton': 'clear_left.png',
         }):
             if v not in pcache:
                 p = I(v)
@@ -1242,7 +1246,7 @@ def elided_text(text, font=None, width=300, pos='middle'):
     from PyQt5.Qt import QFontMetrics, QApplication
     fm = QApplication.fontMetrics() if font is None else (font if isinstance(font, QFontMetrics) else QFontMetrics(font))
     delta = 4
-    ellipsis = u'\u2026'
+    ellipsis = '\u2026'
 
     def remove_middle(x):
         mid = len(x) // 2
@@ -1361,7 +1365,7 @@ def set_app_uid(val):
     try:
         AppUserModelID(unicode_type(val))
     except Exception as err:
-        prints(u'Failed to set app uid with error:', as_unicode(err))
+        prints('Failed to set app uid with error:', as_unicode(err))
         return False
     return True
 

src/calibre/gui2/actions/__init__.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -19,7 +20,7 @@ from polyglot.builtins import unicode_type, string_or_bytes
 
 
 def menu_action_unique_name(plugin, unique_name):
-    return u'%s : menu action : %s'%(plugin.unique_name, unique_name)
+    return '%s : menu action : %s'%(plugin.unique_name, unique_name)
 
 
 class InterfaceAction(QObject):
@@ -151,7 +152,7 @@ class InterfaceAction(QObject):
         bn = self.__class__.__name__
         if getattr(self.interface_action_base_plugin, 'name'):
             bn = self.interface_action_base_plugin.name
-        return u'Interface Action: %s (%s)'%(bn, self.name)
+        return 'Interface Action: %s (%s)'%(bn, self.name)
 
     def create_action(self, spec=None, attr='qaction', shortcut_name=None):
         if spec is None:

src/calibre/gui2/actions/add.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -331,7 +332,8 @@ class AddAction(InterfaceAction):
                     create_book(mi, pt.name, fmt=empty_format)
                     fmts = [pt.name]
                 ids.append(db.import_book(mi, fmts))
-            tuple(map(os.remove, orig_fmts))
+            for path in orig_fmts:
+                os.remove(path)
             self.refresh_gui(num)
             if ids:
                 ids.reverse()

src/calibre/gui2/actions/add_to_library.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/annotate.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/catalog.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -85,7 +86,7 @@ class GenerateCatalogAction(InterfaceAction):
             id = self.gui.library_view.model().add_catalog(job.catalog_file_path, job.catalog_title)
             self.gui.library_view.model().beginResetModel(), self.gui.library_view.model().endResetModel()
             if job.catalog_sync:
-                sync = dynamic.get('catalogs_to_be_synced', set([]))
+                sync = dynamic.get('catalogs_to_be_synced', set())
                 sync.add(id)
                 dynamic.set('catalogs_to_be_synced', sync)
         self.gui.status_bar.show_message(_('Catalog generated.'), 3000)

src/calibre/gui2/actions/choose_library.py

@@ -1,7 +1,7 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
-from __future__ import print_function
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
@@ -252,7 +252,7 @@ class ChooseLibraryAction(InterfaceAction):
         for i in range(5):
             ac = self.create_action(spec=('', None, None, None),
                     attr='switch_action%d'%i)
-            ac.setObjectName(str(i))
+            ac.setObjectName(unicode_type(i))
             self.switch_actions.append(ac)
             ac.setVisible(False)
             connect_lambda(ac.triggered, self, lambda self:
@@ -329,7 +329,7 @@ class ChooseLibraryAction(InterfaceAction):
             self.prev_lname = self.last_lname
             self.last_lname = lname
         if len(lname) > 16:
-            lname = lname[:16] + u'…'
+            lname = lname[:16] + '…'
         a = self.qaction
         a.setText(lname.replace('&', '&&&'))  # I have no idea why this requires a triple ampersand
         self.update_tooltip(db.count())

src/calibre/gui2/actions/convert.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -40,7 +41,7 @@ class ConvertAction(InterfaceAction):
     def drop_event(self, event, mime_data):
         mime = 'application/calibre+from_library'
         if mime_data.hasFormat(mime):
-            self.dropped_ids = tuple(map(int, str(mime_data.data(mime)).split()))
+            self.dropped_ids = tuple(map(int, mime_data.data(mime).data().split()))
             QTimer.singleShot(1, self.do_drop)
             return True
         return False

src/calibre/gui2/actions/copy_to_library.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/delete.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -106,7 +107,7 @@ class DeleteAction(InterfaceAction):
     def drop_event(self, event, mime_data):
         mime = 'application/calibre+from_library'
         if mime_data.hasFormat(mime):
-            self.dropped_ids = tuple(map(int, str(mime_data.data(mime)).split()))
+            self.dropped_ids = tuple(map(int, mime_data.data(mime).data().split()))
             QTimer.singleShot(1, self.do_drop)
             return True
         return False
@@ -165,7 +166,7 @@ class DeleteAction(InterfaceAction):
         if not rows or len(rows) == 0:
             d = error_dialog(self.gui, err_title, _('No book selected'))
             d.exec_()
-            return set([])
+            return set()
         return set(map(self.gui.library_view.model().id, rows))
 
     def remove_format_by_id(self, book_id, fmt):

src/calibre/gui2/actions/device.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -12,7 +13,7 @@ from calibre.gui2.actions import InterfaceAction
 from calibre.gui2.dialogs.smartdevice import SmartdeviceDialog
 from calibre.utils.icu import primary_sort_key
 from calibre.utils.smtp import config as email_config
-from polyglot.builtins import unicode_type, map
+from polyglot.builtins import unicode_type
 
 
 class ShareConnMenu(QMenu):  # {{{
@@ -111,7 +112,8 @@ class ShareConnMenu(QMenu):  # {{{
                         (alias or account) + ' ' + _('(delete from library)'))
                 self.email_to_menu.addAction(action1)
                 self.email_to_and_delete_menu.addAction(action2)
-                tuple(map(self.memory.append, (action1, action2)))
+                self.memory.append(action1)
+                self.memory.append(action2)
                 if default:
                     ac = DeviceAction(dest, False, False,
                             I('mail.png'), _('Email to') + ' ' +(alias or
@@ -127,12 +129,14 @@ class ShareConnMenu(QMenu):  # {{{
                     _('Select recipients') + ' ' + _('(delete from library)'))
             self.email_to_menu.addAction(action1)
             self.email_to_and_delete_menu.addAction(action2)
-            tuple(map(self.memory.append, (action1, action2)))
+            self.memory.append(action1)
+            self.memory.append(action2)
             tac1 = DeviceAction('choosemail:', False, False, I('mail.png'),
                     _('Email to selected recipients...'))
             self.addAction(tac1)
             tac1.a_s.connect(sync_menu.action_triggered)
-            self.memory.append(tac1), self.email_actions.append(tac1)
+            self.memory.append(tac1)
+            self.email_actions.append(tac1)
             ac = self.addMenu(self.email_to_and_delete_menu)
             self.email_actions.append(ac)
             action1.a_s.connect(sync_menu.action_triggered)

src/calibre/gui2/actions/edit_collections.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/edit_metadata.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -51,7 +52,7 @@ class EditMetadataAction(InterfaceAction):
     def drop_event(self, event, mime_data):
         mime = 'application/calibre+from_library'
         if mime_data.hasFormat(mime):
-            self.dropped_ids = tuple(map(int, str(mime_data.data(mime)).split()))
+            self.dropped_ids = tuple(map(int, mime_data.data(mime).data().split()))
             QTimer.singleShot(1, self.do_drop)
             return True
         return False
@@ -648,7 +649,7 @@ class EditMetadataAction(InterfaceAction):
                 if not dest_mi.comments:
                     dest_mi.comments = src_mi.comments
                 else:
-                    dest_mi.comments = unicode_type(dest_mi.comments) + u'\n\n' + unicode_type(src_mi.comments)
+                    dest_mi.comments = unicode_type(dest_mi.comments) + '\n\n' + unicode_type(src_mi.comments)
             if src_mi.title and (not dest_mi.title or dest_mi.title == _('Unknown')):
                 dest_mi.title = src_mi.title
             if (src_mi.authors and src_mi.authors[0] != _('Unknown')) and (not dest_mi.authors or dest_mi.authors[0] == _('Unknown')):
@@ -701,7 +702,7 @@ class EditMetadataAction(InterfaceAction):
                     if not dest_value:
                         db.set_custom(dest_id, src_value, num=colnum)
                     else:
-                        dest_value = unicode_type(dest_value) + u'\n\n' + unicode_type(src_value)
+                        dest_value = unicode_type(dest_value) + '\n\n' + unicode_type(src_value)
                         db.set_custom(dest_id, dest_value, num=colnum)
                 if (dt in {'bool', 'int', 'float', 'rating', 'datetime'} and dest_value is None):
                     db.set_custom(dest_id, src_value, num=colnum)

src/calibre/gui2/actions/embed.py

@@ -37,7 +37,7 @@ class EmbedAction(InterfaceAction):
     def drop_event(self, event, mime_data):
         mime = 'application/calibre+from_library'
         if mime_data.hasFormat(mime):
-            self.dropped_ids = tuple(map(int, str(mime_data.data(mime)).split()))
+            self.dropped_ids = tuple(map(int, mime_data.data(mime).data().split()))
             QTimer.singleShot(1, self.do_drop)
             return True
         return False

src/calibre/gui2/actions/fetch_news.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/help.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -22,6 +23,3 @@ class HelpAction(InterfaceAction):
 
     def show_help(self, *args):
         open_url(QUrl(localize_user_manual_link('https://manual.calibre-ebook.com')))
-
-
-

src/calibre/gui2/actions/mark_books.py

@@ -39,7 +39,7 @@ class MarkBooksAction(InterfaceAction):
     def drop_event(self, event, mime_data):
         mime = 'application/calibre+from_library'
         if mime_data.hasFormat(mime):
-            self.dropped_ids = tuple(map(int, str(mime_data.data(mime)).split()))
+            self.dropped_ids = tuple(map(int, mime_data.data(mime).data().split()))
             QTimer.singleShot(1, self.do_drop)
             return True
         return False

src/calibre/gui2/actions/next_match.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/open.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -24,5 +25,3 @@ class OpenFolderAction(InterfaceAction):
         enabled = loc == 'library'
         self.qaction.setEnabled(enabled)
         self.menuless_qaction.setEnabled(enabled)
-
-

src/calibre/gui2/actions/polish.py

@@ -420,7 +420,7 @@ class PolishAction(InterfaceAction):
     def drop_event(self, event, mime_data):
         mime = 'application/calibre+from_library'
         if mime_data.hasFormat(mime):
-            self.dropped_ids = tuple(map(int, str(mime_data.data(mime)).split()))
+            self.dropped_ids = tuple(map(int, mime_data.data(mime).data().split()))
             QTimer.singleShot(1, self.do_drop)
             return True
         return False

src/calibre/gui2/actions/preferences.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/restart.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -19,5 +20,3 @@ class RestartAction(InterfaceAction):
 
     def restart(self, *args):
         self.gui.quit(restart=True)
-
-

src/calibre/gui2/actions/save_to_disk.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -7,12 +8,11 @@ __docformat__ = 'restructuredtext en'
 
 import os, numbers
 from functools import partial
-from polyglot.builtins import itervalues, map
-
 
 from calibre.utils.config import prefs
 from calibre.gui2 import error_dialog, Dispatcher, choose_dir
 from calibre.gui2.actions import InterfaceAction
+from polyglot.builtins import itervalues, map
 
 
 class SaveToDiskAction(InterfaceAction):

src/calibre/gui2/actions/show_book_details.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/show_quickview.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/show_template_tester.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/similar_books.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/actions/toc_edit.py

@@ -87,7 +87,7 @@ class ToCEditAction(InterfaceAction):
     def drop_event(self, event, mime_data):
         mime = 'application/calibre+from_library'
         if mime_data.hasFormat(mime):
-            self.dropped_ids = tuple(map(int, str(mime_data.data(mime)).split()))
+            self.dropped_ids = tuple(map(int, mime_data.data(mime).data().split()))
             QTimer.singleShot(1, self.do_drop)
             return True
         return False

src/calibre/gui2/actions/tweak_epub.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -74,7 +75,7 @@ class TweakEpubAction(InterfaceAction):
     def drop_event(self, event, mime_data):
         mime = 'application/calibre+from_library'
         if mime_data.hasFormat(mime):
-            self.dropped_ids = tuple(map(int, str(mime_data.data(mime)).split()))
+            self.dropped_ids = tuple(map(int, mime_data.data(mime).data().split()))
             QTimer.singleShot(1, self.do_drop)
             return True
         return False

src/calibre/gui2/actions/unpack_book.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -308,7 +309,7 @@ class UnpackBookAction(InterfaceAction):
     def drop_event(self, event, mime_data):
         mime = 'application/calibre+from_library'
         if mime_data.hasFormat(mime):
-            self.dropped_ids = tuple(map(int, str(mime_data.data(mime)).split()))
+            self.dropped_ids = tuple(map(int, mime_data.data(mime).data().split()))
             QTimer.singleShot(1, self.do_drop)
             return True
         return False

src/calibre/gui2/actions/view.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -166,7 +167,7 @@ class ViewAction(InterfaceAction):
         rows = [r.row() for r in rows]
         book_ids = [db.id(r) for r in rows]
         formats = [[x.upper() for x in db.new_api.formats(book_id)] for book_id in book_ids]
-        all_fmts = set([])
+        all_fmts = set()
         for x in formats:
             if x:
                 for f in x:

src/calibre/gui2/bars.py

@@ -286,10 +286,10 @@ class ToolBar(QToolBar):  # {{{
             event.ignore()
 
     def dropEvent(self, event):
-        data = event.mimeData()
+        md = event.mimeData()
         mime = 'application/calibre+from_library'
-        if data.hasFormat(mime):
+        if md.hasFormat(mime):
-            ids = list(map(int, str(data.data(mime)).split()))
+            ids = list(map(int, md.data(mime).data().split()))
             tgt = None
             for ac in self.location_manager.available_actions:
                 w = self.widgetForAction(ac)
@@ -303,8 +303,8 @@ class ToolBar(QToolBar):  # {{{
                 return
 
         mime = 'application/calibre+from_device'
-        if data.hasFormat(mime):
+        if md.hasFormat(mime):
-            paths = [unicode_type(u.toLocalFile()) for u in data.urls()]
+            paths = [unicode_type(u.toLocalFile()) for u in md.urls()]
             if paths:
                 self.gui.iactions['Add Books'].add_books_from_device(
                         self.gui.current_view(), paths=paths)
@@ -312,7 +312,7 @@ class ToolBar(QToolBar):  # {{{
                 return
 
         # Give added_actions an opportunity to process the drag&drop event
-        if self.check_iactions_for_drag(event, data, 'drop_event'):
+        if self.check_iactions_for_drag(event, md, 'drop_event'):
             event.accept()
         else:
             event.ignore()

src/calibre/gui2/catalog/catalog_bibtex.py

@@ -1,16 +1,17 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
 
+from PyQt5.Qt import QWidget, QListWidgetItem
+
 from calibre.gui2 import gprefs
 from calibre.gui2.catalog.catalog_bibtex_ui import Ui_Form
 from polyglot.builtins import unicode_type, range
-from PyQt5.Qt import QWidget, QListWidgetItem
 
 
 class PluginWidget(QWidget, Ui_Form):

src/calibre/gui2/catalog/catalog_csv_xml.py

@@ -1,15 +1,16 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
+from PyQt5.Qt import QWidget, QListWidgetItem, Qt, QVBoxLayout, QLabel, QListWidget
+
 from calibre.gui2 import gprefs
 from calibre.gui2.ui import get_gui
 from polyglot.builtins import unicode_type, range
-from PyQt5.Qt import QWidget, QListWidgetItem, Qt, QVBoxLayout, QLabel, QListWidget
 
 
 def get_saved_field_data(name, all_fields):

src/calibre/gui2/catalog/catalog_epub_mobi.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import print_function
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -15,7 +15,7 @@ from calibre.gui2 import gprefs, open_url, question_dialog, error_dialog
 from calibre.utils.config import JSONConfig
 from calibre.utils.icu import sort_key
 from calibre.utils.localization import localize_user_manual_link
-from polyglot.builtins import unicode_type, zip, range
+from polyglot.builtins import native_string_type, unicode_type, zip, range
 
 from .catalog_epub_mobi_ui import Ui_Form
 from PyQt5.Qt import (Qt, QAbstractItemView, QCheckBox, QComboBox,
@@ -115,7 +115,7 @@ class PluginWidget(QWidget,Ui_Form):
                                'name':_('Wishlist item'),
                                'field':_('Tags'),
                                'pattern':'Wishlist',
-                               'prefix':u'\u00d7'},],
+                               'prefix':'\u00d7'},],
                              ['table_widget','table_widget']))
 
         self.OPTION_FIELDS = option_fields
@@ -423,7 +423,7 @@ class PluginWidget(QWidget,Ui_Form):
         # Hook Preset signals
         self.preset_delete_pb.clicked.connect(self.preset_remove)
         self.preset_save_pb.clicked.connect(self.preset_save)
-        self.preset_field.currentIndexChanged[str].connect(self.preset_change)
+        self.preset_field.currentIndexChanged[native_string_type].connect(self.preset_change)
 
         self.blocking_all_signals = False
 
@@ -615,7 +615,7 @@ class PluginWidget(QWidget,Ui_Form):
         # Populate the Presets combo box
         self.presets = JSONConfig("catalog_presets")
         self.preset_field.addItem("")
-        self.preset_field_values = sorted([p for p in self.presets], key=sort_key)
+        self.preset_field_values = sorted(self.presets, key=sort_key)
         self.preset_field.addItems(self.preset_field_values)
 
     def preset_change(self, item_name):
@@ -1338,127 +1338,127 @@ class PrefixRules(GenericRulesTable):
 
         # Create a list of prefixes for user selection
         raw_prefix_list = [
-            ('Ampersand',u'&'),
+            ('Ampersand', '&'),
-            ('Angle left double',u'\u00ab'),
+            ('Angle left double', '\u00ab'),
-            ('Angle left',u'\u2039'),
+            ('Angle left', '\u2039'),
-            ('Angle right double',u'\u00bb'),
+            ('Angle right double', '\u00bb'),
-            ('Angle right',u'\u203a'),
+            ('Angle right', '\u203a'),
-            ('Arrow carriage return',u'\u21b5'),
+            ('Arrow carriage return', '\u21b5'),
-            ('Arrow double',u'\u2194'),
+            ('Arrow double', '\u2194'),
-            ('Arrow down',u'\u2193'),
+            ('Arrow down', '\u2193'),
-            ('Arrow left',u'\u2190'),
+            ('Arrow left', '\u2190'),
-            ('Arrow right',u'\u2192'),
+            ('Arrow right', '\u2192'),
-            ('Arrow up',u'\u2191'),
+            ('Arrow up', '\u2191'),
-            ('Asterisk',u'*'),
+            ('Asterisk', '*'),
-            ('At sign',u'@'),
+            ('At sign', '@'),
-            ('Bullet smallest',u'\u22c5'),
+            ('Bullet smallest', '\u22c5'),
-            ('Bullet small',u'\u00b7'),
+            ('Bullet small', '\u00b7'),
-            ('Bullet',u'\u2022'),
+            ('Bullet', '\u2022'),
-            ('Cards clubs',u'\u2663'),
+            ('Cards clubs', '\u2663'),
-            ('Cards diamonds',u'\u2666'),
+            ('Cards diamonds', '\u2666'),
-            ('Cards hearts',u'\u2665'),
+            ('Cards hearts', '\u2665'),
-            ('Cards spades',u'\u2660'),
+            ('Cards spades', '\u2660'),
-            ('Caret',u'^'),
+            ('Caret', '^'),
-            ('Checkmark',u'\u2713'),
+            ('Checkmark', '\u2713'),
-            ('Copyright circle c',u'\u00a9'),
+            ('Copyright circle c', '\u00a9'),
-            ('Copyright circle r',u'\u00ae'),
+            ('Copyright circle r', '\u00ae'),
-            ('Copyright trademark',u'\u2122'),
+            ('Copyright trademark', '\u2122'),
-            ('Currency cent',u'\u00a2'),
+            ('Currency cent', '\u00a2'),
-            ('Currency dollar',u'$'),
+            ('Currency dollar', '$'),
-            ('Currency euro',u'\u20ac'),
+            ('Currency euro', '\u20ac'),
-            ('Currency pound',u'\u00a3'),
+            ('Currency pound', '\u00a3'),
-            ('Currency yen',u'\u00a5'),
+            ('Currency yen', '\u00a5'),
-            ('Dagger double',u'\u2021'),
+            ('Dagger double', '\u2021'),
-            ('Dagger',u'\u2020'),
+            ('Dagger', '\u2020'),
-            ('Degree',u'\u00b0'),
+            ('Degree', '\u00b0'),
-            ('Dots3',u'\u2234'),
+            ('Dots3', '\u2234'),
-            ('Hash',u'#'),
+            ('Hash', '#'),
-            ('Infinity',u'\u221e'),
+            ('Infinity', '\u221e'),
-            ('Lozenge',u'\u25ca'),
+            ('Lozenge', '\u25ca'),
-            ('Math divide',u'\u00f7'),
+            ('Math divide', '\u00f7'),
-            ('Math empty',u'\u2205'),
+            ('Math empty', '\u2205'),
-            ('Math equals',u'='),
+            ('Math equals', '='),
-            ('Math minus',u'\u2212'),
+            ('Math minus', '\u2212'),
-            ('Math plus circled',u'\u2295'),
+            ('Math plus circled', '\u2295'),
-            ('Math times circled',u'\u2297'),
+            ('Math times circled', '\u2297'),
-            ('Math times',u'\u00d7'),
+            ('Math times', '\u00d7'),
-            ('Paragraph',u'\u00b6'),
+            ('Paragraph', '\u00b6'),
-            ('Percent',u'%'),
+            ('Percent', '%'),
-            ('Plus-or-minus',u'\u00b1'),
+            ('Plus-or-minus', '\u00b1'),
-            ('Plus',u'+'),
+            ('Plus', '+'),
-            ('Punctuation colon',u':'),
+            ('Punctuation colon', ':'),
-            ('Punctuation colon-semi',u';'),
+            ('Punctuation colon-semi', ';'),
-            ('Punctuation exclamation',u'!'),
+            ('Punctuation exclamation', '!'),
-            ('Punctuation question',u'?'),
+            ('Punctuation question', '?'),
-            ('Punctuation period',u'.'),
+            ('Punctuation period', '.'),
-            ('Punctuation slash back',u'\\'),
+            ('Punctuation slash back', '\\'),
-            ('Punctuation slash forward',u'/'),
+            ('Punctuation slash forward', '/'),
-            ('Section',u'\u00a7'),
+            ('Section', '\u00a7'),
-            ('Tilde',u'~'),
+            ('Tilde', '~'),
-            ('Vertical bar',u'|'),
+            ('Vertical bar', '|'),
-            ('Vertical bar broken',u'\u00a6'),
+            ('Vertical bar broken', '\u00a6'),
-            ('_0',u'0'),
+            ('_0', '0'),
-            ('_1',u'1'),
+            ('_1', '1'),
-            ('_2',u'2'),
+            ('_2', '2'),
-            ('_3',u'3'),
+            ('_3', '3'),
-            ('_4',u'4'),
+            ('_4', '4'),
-            ('_5',u'5'),
+            ('_5', '5'),
-            ('_6',u'6'),
+            ('_6', '6'),
-            ('_7',u'7'),
+            ('_7', '7'),
-            ('_8',u'8'),
+            ('_8', '8'),
-            ('_9',u'9'),
+            ('_9', '9'),
-            ('_A',u'A'),
+            ('_A', 'A'),
-            ('_B',u'B'),
+            ('_B', 'B'),
-            ('_C',u'C'),
+            ('_C', 'C'),
-            ('_D',u'D'),
+            ('_D', 'D'),
-            ('_E',u'E'),
+            ('_E', 'E'),
-            ('_F',u'F'),
+            ('_F', 'F'),
-            ('_G',u'G'),
+            ('_G', 'G'),
-            ('_H',u'H'),
+            ('_H', 'H'),
-            ('_I',u'I'),
+            ('_I', 'I'),
-            ('_J',u'J'),
+            ('_J', 'J'),
-            ('_K',u'K'),
+            ('_K', 'K'),
-            ('_L',u'L'),
+            ('_L', 'L'),
-            ('_M',u'M'),
+            ('_M', 'M'),
-            ('_N',u'N'),
+            ('_N', 'N'),
-            ('_O',u'O'),
+            ('_O', 'O'),
-            ('_P',u'P'),
+            ('_P', 'P'),
-            ('_Q',u'Q'),
+            ('_Q', 'Q'),
-            ('_R',u'R'),
+            ('_R', 'R'),
-            ('_S',u'S'),
+            ('_S', 'S'),
-            ('_T',u'T'),
+            ('_T', 'T'),
-            ('_U',u'U'),
+            ('_U', 'U'),
-            ('_V',u'V'),
+            ('_V', 'V'),
-            ('_W',u'W'),
+            ('_W', 'W'),
-            ('_X',u'X'),
+            ('_X', 'X'),
-            ('_Y',u'Y'),
+            ('_Y', 'Y'),
-            ('_Z',u'Z'),
+            ('_Z', 'Z'),
-            ('_a',u'a'),
+            ('_a', 'a'),
-            ('_b',u'b'),
+            ('_b', 'b'),
-            ('_c',u'c'),
+            ('_c', 'c'),
-            ('_d',u'd'),
+            ('_d', 'd'),
-            ('_e',u'e'),
+            ('_e', 'e'),
-            ('_f',u'f'),
+            ('_f', 'f'),
-            ('_g',u'g'),
+            ('_g', 'g'),
-            ('_h',u'h'),
+            ('_h', 'h'),
-            ('_i',u'i'),
+            ('_i', 'i'),
-            ('_j',u'j'),
+            ('_j', 'j'),
-            ('_k',u'k'),
+            ('_k', 'k'),
-            ('_l',u'l'),
+            ('_l', 'l'),
-            ('_m',u'm'),
+            ('_m', 'm'),
-            ('_n',u'n'),
+            ('_n', 'n'),
-            ('_o',u'o'),
+            ('_o', 'o'),
-            ('_p',u'p'),
+            ('_p', 'p'),
-            ('_q',u'q'),
+            ('_q', 'q'),
-            ('_r',u'r'),
+            ('_r', 'r'),
-            ('_s',u's'),
+            ('_s', 's'),
-            ('_t',u't'),
+            ('_t', 't'),
-            ('_u',u'u'),
+            ('_u', 'u'),
-            ('_v',u'v'),
+            ('_v', 'v'),
-            ('_w',u'w'),
+            ('_w', 'w'),
-            ('_x',u'x'),
+            ('_x', 'x'),
-            ('_y',u'y'),
+            ('_y', 'y'),
-            ('_z',u'z'),
+            ('_z', 'z'),
             ]
         raw_prefix_list = sorted(raw_prefix_list, key=prefix_sorter)
         self.prefix_list = [x[1] for x in raw_prefix_list]

src/calibre/gui2/comments_editor.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -338,7 +339,7 @@ class EditorWidget(QWebView, LineEditECM):  # {{{
 
     @property
     def html(self):
-        ans = u''
+        ans = ''
         try:
             if not self.page().mainFrame().documentElement().findFirst('meta[name="calibre-dont-sanitize"]').isNull():
                 # Bypass cleanup if special meta tag exists
@@ -364,9 +365,9 @@ class EditorWidget(QWebView, LineEditECM):  # {{{
                     x.tag not in ('script', 'style')]
 
             if len(elems) > 1:
-                ans = u'<div>%s</div>'%(u''.join(elems))
+                ans = '<div>%s</div>'%(''.join(elems))
             else:
-                ans = u''.join(elems)
+                ans = ''.join(elems)
                 if not ans.startswith('<'):
                     ans = '<p>%s</p>'%ans
             ans = xml_replace_entities(ans)
@@ -482,7 +483,7 @@ class Highlighter(QSyntaxHighlighter):
             if state == State_Comment:
                 start = pos
                 while pos < len_:
-                    if text[pos:pos+3] == u"-->":
+                    if text[pos:pos+3] == "-->":
                         pos += 3
                         state = State_Text
                         break
@@ -495,7 +496,7 @@ class Highlighter(QSyntaxHighlighter):
                 while pos < len_:
                     ch = text[pos]
                     pos += 1
-                    if ch == u'>':
+                    if ch == '>':
                         state = State_Text
                         break
                 self.setFormat(start, pos - start, self.colors['doctype'])
@@ -506,7 +507,7 @@ class Highlighter(QSyntaxHighlighter):
                 while pos < len_:
                     ch = text[pos]
                     pos += 1
-                    if ch == u'>':
+                    if ch == '>':
                         state = State_Text
                         break
                     if not ch.isspace():
@@ -524,7 +525,7 @@ class Highlighter(QSyntaxHighlighter):
                         pos -= 1
                         state = State_InsideTag
                         break
-                    if ch == u'>':
+                    if ch == '>':
                         state = State_Text
                         break
                 self.setFormat(start, pos - start, self.colors['tag'])
@@ -537,10 +538,10 @@ class Highlighter(QSyntaxHighlighter):
                     ch = text[pos]
                     pos += 1
 
-                    if ch == u'/':
+                    if ch == '/':
                         continue
 
-                    if ch == u'>':
+                    if ch == '>':
                         state = State_Text
                         break
 
@@ -557,11 +558,11 @@ class Highlighter(QSyntaxHighlighter):
                     ch = text[pos]
                     pos += 1
 
-                    if ch == u'=':
+                    if ch == '=':
                         state = State_AttributeValue
                         break
 
-                    if ch in (u'>', u'/'):
+                    if ch in ('>', '/'):
                         state = State_InsideTag
                         break
 
@@ -577,12 +578,12 @@ class Highlighter(QSyntaxHighlighter):
                     pos += 1
 
                     # handle opening single quote
-                    if ch == u"'":
+                    if ch == "'":
                         state = State_SingleQuote
                         break
 
                     # handle opening double quote
-                    if ch == u'"':
+                    if ch == '"':
                         state = State_DoubleQuote
                         break
 
@@ -597,7 +598,7 @@ class Highlighter(QSyntaxHighlighter):
                         ch = text[pos]
                         if ch.isspace():
                             break
-                        if ch in (u'>', u'/'):
+                        if ch in ('>', '/'):
                             break
                         pos += 1
                     state = State_InsideTag
@@ -610,7 +611,7 @@ class Highlighter(QSyntaxHighlighter):
                 while pos < len_:
                     ch = text[pos]
                     pos += 1
-                    if ch == u"'":
+                    if ch == "'":
                         break
 
                 state = State_InsideTag
@@ -624,7 +625,7 @@ class Highlighter(QSyntaxHighlighter):
                 while pos < len_:
                     ch = text[pos]
                     pos += 1
-                    if ch == u'"':
+                    if ch == '"':
                         break
 
                 state = State_InsideTag
@@ -635,18 +636,18 @@ class Highlighter(QSyntaxHighlighter):
                 # State_Text and default
                 while pos < len_:
                     ch = text[pos]
-                    if ch == u'<':
+                    if ch == '<':
-                        if text[pos:pos+4] == u"<!--":
+                        if text[pos:pos+4] == "<!--":
                             state = State_Comment
                         else:
-                            if text[pos:pos+9].upper() == u"<!DOCTYPE":
+                            if text[pos:pos+9].upper() == "<!DOCTYPE":
                                 state = State_DocType
                             else:
                                 state = State_TagStart
                         break
-                    elif ch == u'&':
+                    elif ch == '&':
                         start = pos
-                        while pos < len_ and text[pos] != u';':
+                        while pos < len_ and text[pos] != ';':
                             self.setFormat(start, pos - start,
                                     self.colors['entity'])
                             pos += 1

src/calibre/gui2/convert/azw3_output.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/convert/comic_input.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/convert/docx_output.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__ = 'GPL 3'
 __copyright__ = '2009, John Schember <john@nachtimwald.com>'

src/calibre/gui2/convert/epub_output.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/convert/fb2_input.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__ = 'GPL 3'
 __copyright__ = '2009, John Schember <john@nachtimwald.com>'

src/calibre/gui2/convert/fb2_output.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__ = 'GPL 3'
 __copyright__ = '2009, John Schember <john@nachtimwald.com>'

src/calibre/gui2/convert/htmlz_output.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__ = 'GPL 3'
 __copyright__ = '2009, John Schember <john@nachtimwald.com>'

src/calibre/gui2/convert/lrf_output.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/convert/mobi_output.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'

src/calibre/gui2/convert/pdb_output.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__ = 'GPL 3'
 __copyright__ = '2009, John Schember <john@nachtimwald.com>'

src/calibre/gui2/convert/txtz_output.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__ = 'GPL 3'
 __copyright__ = '2011, John Schember <john@nachtimwald.com>'

src/calibre/gui2/dbus_export/utils.py

@@ -128,7 +128,7 @@ def icon_to_dbus_menu_icon(icon, size=32):
     buf = QBuffer(ba)
     buf.open(QBuffer.WriteOnly)
     icon.pixmap(32).save(buf, 'PNG')
-    return dbus.ByteArray(bytes((ba.data())))
+    return dbus.ByteArray(ba)
 
 
 def setup_for_cli_run():

src/calibre/gui2/device.py

@@ -1,4 +1,5 @@
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function, unicode_literals
+
 __license__   = 'GPL v3'
 __copyright__ = '2008, Kovid Goyal <kovid at kovidgoyal.net>'
 
@@ -34,7 +35,7 @@ from calibre.utils.config import tweaks, device_prefs
 from calibre.utils.img import scale_image
 from calibre.library.save_to_disk import find_plugboard
 from calibre.ptempfile import PersistentTemporaryFile, force_unicode as filename_to_unicode
-from polyglot.builtins import unicode_type, string_or_bytes
+from polyglot.builtins import unicode_type, string_or_unicode
 from polyglot import queue
 # }}}
 
@@ -209,7 +210,7 @@ class DeviceManager(Thread):  # {{{
                 tb = traceback.format_exc()
                 if DEBUG or tb not in self.reported_errors:
                     self.reported_errors.add(tb)
-                    prints('Unable to open device', str(dev))
+                    prints('Unable to open device', unicode_type(dev))
                     prints(tb)
                 continue
             self.after_device_connect(dev, device_kind)
@@ -472,7 +473,7 @@ class DeviceManager(Thread):  # {{{
         info = self.device.get_device_information(end_session=False)
         if len(info) < 5:
             info = tuple(list(info) + [{}])
-        info = [i.replace('\x00', '').replace('\x01', '') if isinstance(i, string_or_bytes) else i
+        info = [i.replace('\x00', '').replace('\x01', '') if isinstance(i, string_or_unicode) else i
                  for i in info]
         cp = self.device.card_prefix(end_session=False)
         fs = self.device.free_space()
@@ -604,7 +605,7 @@ class DeviceManager(Thread):  # {{{
                      metadata=None, plugboards=None, add_as_step_to_job=None):
         desc = ngettext('Upload one book to the device', 'Upload {} books to the device', len(names)).format(len(names))
         if titles:
-            desc += u': ' + u', '.join(titles)
+            desc += ': ' + ', '.join(titles)
         return self.create_job_step(self._upload_books, done, to_job=add_as_step_to_job,
                                args=[files, names],
                 kwargs={'on_card':on_card,'metadata':metadata,'plugboards':plugboards}, description=desc)
@@ -930,7 +931,7 @@ class DeviceMixin(object):  # {{{
         d.show()
 
     def auto_convert_question(self, msg, autos):
-        autos = u'\n'.join(map(unicode_type, map(force_unicode, autos)))
+        autos = '\n'.join(map(unicode_type, map(force_unicode, autos)))
         return self.ask_a_yes_no_question(
                 _('No suitable formats'), msg,
                 ans_when_user_unavailable=True,
@@ -1343,7 +1344,7 @@ class DeviceMixin(object):  # {{{
                         self.iactions['Convert Books'].auto_convert_catalogs(auto, format)
             files = [f for f in files if f is not None]
             if not files:
-                dynamic.set('catalogs_to_be_synced', set([]))
+                dynamic.set('catalogs_to_be_synced', set())
                 return
             metadata = self.library_view.model().metadata_for(ids)
             names = []
@@ -1355,7 +1356,7 @@ class DeviceMixin(object):  # {{{
                 names.append('%s_%d%s'%(prefix, id,
                     os.path.splitext(files[-1])[1]))
                 self.update_thumbnail(mi)
-            dynamic.set('catalogs_to_be_synced', set([]))
+            dynamic.set('catalogs_to_be_synced', set())
             if files:
                 remove = []
                 space = {self.location_manager.free[0] : None,
@@ -1627,7 +1628,7 @@ class DeviceMixin(object):  # {{{
 
         if job.exception is not None:
             if isinstance(job.exception, FreeSpaceError):
-                where = 'in main memory.' if 'memory' in str(job.exception) \
+                where = 'in main memory.' if 'memory' in unicode_type(job.exception) \
                         else 'on the storage card.'
                 titles = '\n'.join(['<li>'+mi.title+'</li>'
                                     for mi in metadata])

src/calibre/gui2/device_drivers/configwidget.py

@@ -156,7 +156,7 @@ class ConfigWidget(QWidget, Ui_ConfigWidget):
         formats = set(self.format_map())
         extra = formats - set(self.calibre_known_formats)
         if extra:
-            fmts = sorted([x.upper() for x in extra])
+            fmts = sorted((x.upper() for x in extra))
             if not question_dialog(self, _('Unknown formats'),
                     _('You have enabled the <b>{0}</b> formats for'
                         ' your {1}. The {1} may not support them.'

src/calibre/gui2/dialogs/catalog.py

@@ -96,7 +96,7 @@ class Catalog(QDialog, Ui_Dialog):
         self.widgets = sorted(self.widgets, key=lambda x: x.TITLE)
 
         # Generate a sorted list of installed catalog formats/sync_enabled pairs
-        fmts = sorted([x[0] for x in self.fmts])
+        fmts = sorted((x[0] for x in self.fmts))
 
         self.sync_enabled_formats = []
         for fmt in self.fmts:

src/calibre/gui2/dialogs/metadata_bulk.py

@@ -743,7 +743,7 @@ class MetadataBulkDialog(QDialog, Ui_MetadataBulkDialog):
         self.queries = JSONConfig("search_replace_queries")
         self.saved_search_name = ''
         self.query_field.addItem("")
-        self.query_field_values = sorted([q for q in self.queries], key=sort_key)
+        self.query_field_values = sorted(self.queries, key=sort_key)
         self.query_field.addItems(self.query_field_values)
         self.query_field.currentIndexChanged[str].connect(self.s_r_query_change)
         self.query_field.setCurrentIndex(0)
@@ -1323,7 +1323,7 @@ class MetadataBulkDialog(QDialog, Ui_MetadataBulkDialog):
             self.query_field.blockSignals(True)
             self.query_field.clear()
             self.query_field.addItem('')
-            self.query_field_values = sorted([q for q in self.queries], key=sort_key)
+            self.query_field_values = sorted(self.queries, key=sort_key)
             self.query_field.addItems(self.query_field_values)
             self.query_field.blockSignals(False)
         self.query_field.setCurrentIndex(self.query_field.findText(name))

src/calibre/gui2/library/alternate_views.py

@@ -76,7 +76,7 @@ def image_to_data(image):  # {{{
     buf.open(QBuffer.WriteOnly)
     if not image.save(buf, CACHE_FORMAT):
         raise EncodeError('Failed to encode thumbnail')
-    ret = bytes(ba.data())
+    ret = ba.data()
     buf.close()
     return ret
 # }}}

src/calibre/gui2/main.py

@@ -136,7 +136,7 @@ def get_default_library_path():
             fname.encode(filesystem_encoding)
         except Exception:
             fname = 'Calibre Library'
-    x = os.path.expanduser('~'+os.sep+fname)
+    x = os.path.expanduser(os.path.join('~', fname))
     if not os.path.exists(x):
         try:
             os.makedirs(x)

src/calibre/gui2/notify.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -44,7 +44,7 @@ class DBUSNotifier(Notifier):
             self._notify = dbus.Interface(session_bus.get_object(server, path), interface)
         except Exception as err:
             self.ok = False
-            self.err = str(err)
+            self.err = unicode_type(err)
         if DEBUG:
             prints(server, 'found' if self.ok else 'not found', 'in', '%.1f' % (time.time() - start), 'seconds')
 

src/calibre/gui2/search_box.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python2
 # vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function, unicode_literals
 
 __license__   = 'GPL v3'
 __copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'
@@ -20,7 +20,7 @@ from calibre.gui2.dialogs.confirm_delete import confirm
 from calibre.gui2.dialogs.saved_search_editor import SavedSearchEditor
 from calibre.gui2.dialogs.search import SearchDialog
 from calibre.utils.icu import primary_sort_key
-from polyglot.builtins import unicode_type, string_or_bytes, map, range
+from polyglot.builtins import native_string_type, unicode_type, string_or_bytes, map, range
 
 QT_HIDDEN_CLEAR_ACTION = '_q_qlineeditclearaction'
 
@@ -119,11 +119,11 @@ class SearchBox2(QComboBox):  # {{{
 
         c = self.line_edit.completer()
         c.setCompletionMode(c.PopupCompletion)
-        c.highlighted[str].connect(self.completer_used)
+        c.highlighted[native_string_type].connect(self.completer_used)
 
         self.line_edit.key_pressed.connect(self.key_pressed, type=Qt.DirectConnection)
         # QueuedConnection as workaround for https://bugreports.qt-project.org/browse/QTBUG-40807
-        self.activated[str].connect(self.history_selected, type=Qt.QueuedConnection)
+        self.activated[native_string_type].connect(self.history_selected, type=Qt.QueuedConnection)
         self.setEditable(True)
         self.as_you_type = True
         self.timer = QTimer()
@@ -272,7 +272,7 @@ class SearchBox2(QComboBox):  # {{{
 
     def set_search_string(self, txt, store_in_history=False, emit_changed=True):
         if not store_in_history:
-            self.activated[str].disconnect()
+            self.activated[native_string_type].disconnect()
         try:
             self.setFocus(Qt.OtherFocusReason)
             if not txt:

src/calibre/gui2/store/stores/whsmith_uk_plugin.py

@@ -28,7 +28,7 @@ from calibre.gui2.store.web_store_dialog import WebStoreDialog
 class WHSmithUKStore(BasicStoreConfig, StorePlugin):
 
     def open(self, parent=None, detail_item=None, external=False):
-        url = 'http://www.whsmith.co.uk/'
+        url = 'https://www.whsmith.co.uk/'
         url_details = ''
 
         if external or self.config.get('open_external', False):
@@ -45,7 +45,7 @@ class WHSmithUKStore(BasicStoreConfig, StorePlugin):
             d.exec_()
 
     def search(self, query, max_results=10, timeout=60):
-        url = ('http://www.whsmith.co.uk/search?keywordCategoryId=wc_dept_ebooks&results=60'
+        url = ('https://www.whsmith.co.uk/search?keywordCategoryId=wc_dept_ebooks&results=60'
                '&page=1&keywords=' + quote(query))
 
         br = browser()
@@ -59,7 +59,7 @@ class WHSmithUKStore(BasicStoreConfig, StorePlugin):
                 id_ = ''.join(data.xpath('./a[@class="product_image_wrap"]/@href'))
                 if not id_:
                     continue
-                id_ = 'http://www.whsmith.co.uk' + id_
+                id_ = 'https://www.whsmith.co.uk' + id_
                 cover_url = ''.join(data.xpath('.//img[@class="product_image"]/@src'))
                 title = ''.join(data.xpath('.//h4[@class="product_title"]/text()'))
                 author = ', '.join(data.xpath('.//span[@class="product_second"]/text()'))

src/calibre/gui2/store/stores/woblink_plugin.py

@@ -36,7 +36,7 @@ def as_base64(data):
 
 
 def search(query, max_results=10, timeout=60):
-    url = 'http://woblink.com/publication/ajax?mode=none&query=' + quote_plus(query)
+    url = 'https://woblink.com/publication/ajax?mode=none&query=' + quote_plus(query)
     if max_results > 10:
         if max_results > 20:
             url += '&limit=30'
@@ -47,7 +47,7 @@ def search(query, max_results=10, timeout=60):
     rq = Request(url, headers={
         'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8',
         'X-Requested-With': 'XMLHttpRequest',
-        'Referrer':'http://woblink.com/ebooki-kategorie',
+        'Referrer':'https://woblink.com/ebooki-kategorie',
         'Cache-Control':'max-age=0',
     }, data=urlencode({
         'nw_filtry_filtr_zakrescen_formularz[min]':'0',
@@ -89,13 +89,13 @@ class WoblinkStore(BasicStoreConfig, StorePlugin):
 
     def open(self, parent=None, detail_item=None, external=False):
         aff_root = 'https://www.a4b-tracking.com/pl/stat-click-text-link/16/58/'
-        url = 'http://woblink.com/publication'
+        url = 'https://woblink.com/publication'
 
         aff_url = aff_root + as_base64(url)
         detail_url = None
 
         if detail_item:
-            detail_url = aff_root + as_base64('http://woblink.com' + detail_item)
+            detail_url = aff_root + as_base64('https://woblink.com' + detail_item)
 
         if external or self.config.get('open_external', False):
             open_url(QUrl(url_slash_cleaner(detail_url if detail_url else aff_url)))

src/calibre/gui2/store/stores/wolnelektury_plugin.py

@@ -29,7 +29,7 @@ class WolneLekturyStore(BasicStoreConfig, StorePlugin):
 
     def open(self, parent=None, detail_item=None, external=False):
 
-        url = 'http://wolnelektury.pl'
+        url = 'https://wolnelektury.pl'
         detail_url = None
 
         if detail_item:
@@ -44,7 +44,7 @@ class WolneLekturyStore(BasicStoreConfig, StorePlugin):
             d.exec_()
 
     def search(self, query, max_results=10, timeout=60):
-        url = 'http://wolnelektury.pl/szukaj?q=' + quote_plus(query)
+        url = 'https://wolnelektury.pl/szukaj?q=' + quote_plus(query)
 
         br = browser()
 
@@ -69,13 +69,13 @@ class WolneLekturyStore(BasicStoreConfig, StorePlugin):
                 s = SearchResult()
                 for link in data.xpath('.//div[@class="book-box-formats"]/span/a'):
                     ext = ''.join(link.xpath('./text()'))
-                    href = 'http://wolnelektury.pl' + link.get('href')
+                    href = 'https://wolnelektury.pl' + link.get('href')
                     s.downloads[ext] = href
-                s.cover_url = 'http://wolnelektury.pl' + cover_url.strip()
+                s.cover_url = 'https://wolnelektury.pl' + cover_url.strip()
                 s.title = title.strip()
                 s.author = author
                 s.price = price
-                s.detail_item = 'http://wolnelektury.pl' + id
+                s.detail_item = 'https://wolnelektury.pl' + id
                 s.formats = ', '.join(s.downloads.keys())
                 s.drm = SearchResult.DRM_UNLOCKED
 

src/calibre/gui2/store/stores/xinxii_plugin.py

@@ -23,10 +23,10 @@ from calibre.gui2.store.search_result import SearchResult
 
 class XinXiiStore(BasicStoreConfig, OpenSearchOPDSStore):
 
-    open_search_url = 'http://www.xinxii.com/catalog-search/'
+    open_search_url = 'https://www.xinxii.com/catalog-search/'
-    web_url = 'http://xinxii.com/'
+    web_url = 'https://xinxii.com/'
 
-    # http://www.xinxii.com/catalog/
+    # https://www.xinxii.com/catalog/
 
     def search(self, query, max_results=10, timeout=60):
         '''
@@ -42,7 +42,7 @@ class XinXiiStore(BasicStoreConfig, OpenSearchOPDSStore):
         function so this one is modified to remove parts that are used.
         '''
 
-        url = 'http://www.xinxii.com/catalog-search/query/?keywords=' + quote_plus(query)
+        url = 'https://www.xinxii.com/catalog-search/query/?keywords=' + quote_plus(query)
 
         counter = max_results
         br = browser()

src/calibre/gui2/tag_browser/model.py

@@ -857,7 +857,7 @@ class TagsModel(QAbstractItemModel):  # {{{
                                                    fm['datatype'] == 'composite' and
                                                    fm['display'].get('make_category', False)))):
                     mime = 'application/calibre+from_library'
-                    ids = list(map(int, str(md.data(mime)).split()))
+                    ids = list(map(int, md.data(mime).data().split()))
                     self.handle_drop(node, ids)
                     return True
             elif node.type == TagTreeItem.CATEGORY:
@@ -871,7 +871,7 @@ class TagsModel(QAbstractItemModel):  # {{{
                              (fm_src['datatype'] == 'composite' and
                               fm_src['display'].get('make_category', False))):
                         mime = 'application/calibre+from_library'
-                        ids = list(map(int, str(md.data(mime)).split()))
+                        ids = list(map(int, md.data(mime).data().split()))
                         self.handle_user_category_drop(node, ids, md.column_name)
                         return True
         return False

src/calibre/gui2/tools.py

@@ -1,4 +1,6 @@
 #!/usr/bin/env  python2
+from __future__ import absolute_import, division, print_function, unicode_literals
+
 __license__   = 'GPL v3'
 __copyright__ = '2008, Kovid Goyal kovid@kovidgoyal.net'
 __docformat__ = 'restructuredtext en'

src/calibre/gui2/tweak_book/spell.py

@@ -67,7 +67,7 @@ class AddDictionary(QDialog):  # {{{
             download more dictionaries from <a href="{1}">the LibreOffice extensions repository</a>.
             The dictionary will download as an .oxt file. Simply specify the path to the
             downloaded .oxt file here to add the dictionary to {0}.''').format(
-                __appname__, 'http://extensions.libreoffice.org/extension-center?getCategories=Dictionary&getCompatibility=any&sort_on=positive_ratings')+'<p>')  # noqa
+                __appname__, 'https://extensions.libreoffice.org/extension-center?getCategories=Dictionary&getCompatibility=any&sort_on=positive_ratings')+'<p>')  # noqa
         la.setWordWrap(True)
         la.setOpenExternalLinks(True)
         la.setMinimumWidth(450)

src/calibre/gui2/widgets.py

@@ -1,4 +1,5 @@
-from __future__ import print_function
+from __future__ import absolute_import, division, print_function, unicode_literals
+
 __license__   = 'GPL v3'
 __copyright__ = '2008, Kovid Goyal <kovid at kovidgoyal.net>'
 '''
@@ -23,7 +24,7 @@ from calibre.gui2.progress_indicator import ProgressIndicator as _ProgressIndica
 from calibre.gui2.dnd import (dnd_has_image, dnd_get_image, dnd_get_files,
     image_extensions, dnd_has_extension, DownloadDialog)
 from calibre.utils.localization import localize_user_manual_link
-from polyglot.builtins import unicode_type, range
+from polyglot.builtins import native_string_type, unicode_type, range
 
 history = XMLConfig('history')
 
@@ -45,11 +46,11 @@ class ProgressIndicator(QWidget):  # {{{
         pwidth, pheight = view.size().width(), view.size().height()
         self.resize(pwidth, min(pheight, 250))
         if self.pos is None:
-            self.move(0, (pheight-self.size().height())/2.)
+            self.move(0, (pheight-self.size().height())/2)
         else:
             self.move(self.pos[0], self.pos[1])
         self.pi.resize(self.pi.sizeHint())
-        self.pi.move(int((self.size().width()-self.pi.size().width())/2.), 0)
+        self.pi.move(int((self.size().width()-self.pi.size().width())//2), 0)
         self.status.resize(self.size().width(), self.size().height()-self.pi.size().height()-10)
         self.status.move(0, self.pi.size().height()+10)
         self.status.setText('<h1>'+msg+'</h1>')
@@ -137,7 +138,7 @@ class FilenamePattern(QWidget, Ui_Form):  # {{{
             self.series.setText(_('No match'))
 
         if mi.series_index is not None:
-            self.series_index.setText(str(mi.series_index))
+            self.series_index.setText(unicode_type(mi.series_index))
         else:
             self.series_index.setText(_('No match'))
 
@@ -151,7 +152,7 @@ class FilenamePattern(QWidget, Ui_Form):  # {{{
         else:
             self.pubdate.setText(_('No match'))
 
-        self.isbn.setText(_('No match') if mi.isbn is None else str(mi.isbn))
+        self.isbn.setText(_('No match') if mi.isbn is None else unicode_type(mi.isbn))
         self.comments.setText(mi.comments if mi.comments else _('No match'))
 
     def pattern(self):
@@ -304,7 +305,7 @@ def draw_size(p, rect, w, h):
     f = p.font()
     f.setBold(True)
     p.setFont(f)
-    sz = u'\u00a0%d x %d\u00a0'%(w, h)
+    sz = '\u00a0%d x %d\u00a0'%(w, h)
     flags = Qt.AlignBottom|Qt.AlignRight|Qt.TextSingleLine
     szrect = p.boundingRect(rect, flags, sz)
     p.fillRect(szrect.adjusted(0, 0, 0, 4), QColor(0, 0, 0, 200))
@@ -369,8 +370,8 @@ class ImageView(QWidget, ImageDropMixin):
             pmap = pmap.scaled(int(nw*pmap.devicePixelRatio()), int(nh*pmap.devicePixelRatio()), Qt.IgnoreAspectRatio,
                     Qt.SmoothTransformation)
         w, h = int(pmap.width()/pmap.devicePixelRatio()), int(pmap.height()/pmap.devicePixelRatio())
-        x = int(abs(cw - w)/2.)
+        x = int(abs(cw - w)//2)
-        y = int(abs(ch - h)/2.)
+        y = int(abs(ch - h)//2)
         target = QRect(x, y, w, h)
         p = QPainter(self)
         p.setRenderHints(QPainter.Antialiasing | QPainter.SmoothPixmapTransform)
@@ -570,7 +571,7 @@ class CompleteLineEdit(EnLineEdit):  # {{{
         self.completer = ItemsCompleter(self, complete_items)
         self.completer.setCaseSensitivity(Qt.CaseInsensitive)
 
-        self.completer.activated[str].connect(self.complete_text)
+        self.completer.activated[native_string_type].connect(self.complete_text)
 
         self.completer.setWidget(self)
 
@@ -888,13 +889,13 @@ class PythonHighlighter(QSyntaxHighlighter):  # {{{
         self.setFormat(0, textLength,
                        PythonHighlighter.Formats["normal"])
 
-        if text.startswith(u"Traceback") or text.startswith(u"Error: "):
+        if text.startswith("Traceback") or text.startswith("Error: "):
             self.setCurrentBlockState(ERROR)
             self.setFormat(0, textLength,
                            PythonHighlighter.Formats["error"])
             return
         if prevState == ERROR and \
-           not (text.startswith(u'>>>') or text.startswith(u"#")):
+           not (text.startswith('>>>') or text.startswith("#")):
             self.setCurrentBlockState(ERROR)
             self.setFormat(0, textLength,
                            PythonHighlighter.Formats["error"])
@@ -913,18 +914,18 @@ class PythonHighlighter(QSyntaxHighlighter):  # {{{
         # PythonHighlighter.Rules.append((QRegExp(r"#.*"), "comment"))
         if not text:
             pass
-        elif text[0] == u"#":
+        elif text[0] == "#":
             self.setFormat(0, len(text),
                            PythonHighlighter.Formats["comment"])
         else:
             stack = []
             for i, c in enumerate(text):
-                if c in (u'"', u"'"):
+                if c in ('"', "'"):
                     if stack and stack[-1] == c:
                         stack.pop()
                     else:
                         stack.append(c)
-                elif c == u"#" and len(stack) == 0:
+                elif c == "#" and len(stack) == 0:
                     self.setFormat(i, len(text),
                                    PythonHighlighter.Formats["comment"])
                     break

src/calibre/utils/ipc/launch.py

@@ -23,7 +23,7 @@ if iswindows:
     except:
         raise RuntimeError('NUL file missing in windows. This indicates a'
                 ' corrupted windows. You should contact Microsoft'
-                ' for assistance and/or follow the steps described here: http://bytes.com/topic/net/answers/264804-compile-error-null-device-missing')
+                ' for assistance and/or follow the steps described here: https://bytes.com/topic/net/answers/264804-compile-error-null-device-missing')
 
 
 def renice(niceness):

src/calibre/utils/unrar.py

@@ -90,10 +90,10 @@ def extract_member(
 
 def extract_first_alphabetically(stream):
     from calibre.libunzip import sort_key
-    names_ = sorted([
+    names_ = sorted((
         x for x in names(stream)
         if os.path.splitext(x)[1][1:].lower() in {
-            'png', 'jpg', 'jpeg', 'gif', 'webp'}],
+            'png', 'jpg', 'jpeg', 'gif', 'webp'}),
                     key=sort_key)
     return extract_member(stream, name=names_[0], match=None)
 

src/calibre/utils/wmf/__init__.py

@@ -68,4 +68,4 @@ def to_png(bmp):
     buf = QBuffer(ba)
     buf.open(QBuffer.WriteOnly)
     i.save(buf, 'png')
-    return bytes(ba.data())
+    return ba.data()

src/polyglot/builtins.py

@@ -72,6 +72,7 @@ if is_py3:
     codepoint_to_chr = chr
     unicode_type = str
     string_or_bytes = str, bytes
+    string_or_unicode = str
     long_type = int
     raw_input = input
     getcwd = os.getcwd
@@ -126,6 +127,7 @@ else:
     codepoint_to_chr = unichr
     unicode_type = unicode
     string_or_bytes = unicode, bytes
+    string_or_unicode = str, unicode
     long_type = long
     exec_path = execfile
     raw_input = builtins.raw_input