diff --git a/src/calibre/ebooks/pdf/render/gradients.py b/src/calibre/ebooks/pdf/render/gradients.py
index a9532d49ef..5878789ef5 100644
--- a/src/calibre/ebooks/pdf/render/gradients.py
+++ b/src/calibre/ebooks/pdf/render/gradients.py
@@ -11,8 +11,11 @@ import sys, copy
 from future_builtins import map
 from collections import namedtuple
 
-import sip
 from PyQt5.Qt import QLinearGradient, QPointF
+try:
+    from PyQt5 import sip
+except ImportError:
+    import sip
 
 from calibre.ebooks.pdf.render.common import Name, Array, Dictionary
 
@@ -151,4 +154,3 @@ class LinearGradientPattern(Dictionary):
                 stops[-1][0] = base_stops[-1][0]
 
         return start, stop, tuple(Stop(s[0], s[1]) for s in stops)
-
diff --git a/src/calibre/gui2/actions/show_book_details.py b/src/calibre/gui2/actions/show_book_details.py
index cc164bf053..4e4ceac324 100644
--- a/src/calibre/gui2/actions/show_book_details.py
+++ b/src/calibre/gui2/actions/show_book_details.py
@@ -6,6 +6,10 @@ __copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
 from PyQt5.Qt import Qt
+try:
+    from PyQt5 import sip
+except ImportError:
+    import sip
 
 from calibre.gui2.actions import InterfaceAction
 from calibre.gui2.dialogs.book_info import BookInfo
@@ -45,6 +49,5 @@ class ShowBookDetailsAction(InterfaceAction):
         except ValueError:
             pass
         else:
-            import sip
             sip.delete(d)
             del d
diff --git a/src/calibre/gui2/bars.py b/src/calibre/gui2/bars.py
index 4acaf35b52..8b14d37bf4 100644
--- a/src/calibre/gui2/bars.py
+++ b/src/calibre/gui2/bars.py
@@ -8,10 +8,13 @@ __copyright__ = '2011, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
 from functools import partial
-import sip
 from PyQt5.Qt import (
     Qt, QAction, QMenu, QObject, QToolBar, QToolButton, QSize, pyqtSignal,
     QTimer, QPropertyAnimation, QEasingCurve, pyqtProperty, QPainter, QWidget)
+try:
+    from PyQt5 import sip
+except ImportError:
+    import sip
 
 from calibre.constants import isosx
 from calibre.gui2 import gprefs, native_menubar_defaults, config
diff --git a/src/calibre/gui2/catalog/catalog_epub_mobi.py b/src/calibre/gui2/catalog/catalog_epub_mobi.py
index d89909275b..ef1122cc09 100644
--- a/src/calibre/gui2/catalog/catalog_epub_mobi.py
+++ b/src/calibre/gui2/catalog/catalog_epub_mobi.py
@@ -21,6 +21,10 @@ from PyQt5.Qt import (Qt, QAbstractItemView, QCheckBox, QComboBox,
         QDoubleSpinBox, QIcon, QInputDialog, QLineEdit, QRadioButton,
         QSize, QSizePolicy, QTableWidget, QTableWidgetItem, QTextEdit, QToolButton,
         QUrl, QVBoxLayout, QWidget)
+try:
+    from PyQt5 import sip
+except ImportError:
+    import sip
 
 
 class PluginWidget(QWidget,Ui_Form):
@@ -78,7 +82,7 @@ class PluginWidget(QWidget,Ui_Form):
                             ['radio_button' for i in RadioButtonControls])
 
         # LineEditControls
-        option_fields += zip(['exclude_genre'],['\[.+\]|^\+$'],['line_edit'])
+        option_fields += zip(['exclude_genre'],[r'\[.+\]|^\+$'],['line_edit'])
 
         # TextEditControls
         # option_fields += zip(['exclude_genre_results'],['excluded genres will appear here'],['text_edit'])
@@ -966,7 +970,6 @@ class GenericRulesTable(QTableWidget):
                 for i in reversed(range(child.count())):
                     if child.itemAt(i).widget() is not None:
                         child.itemAt(i).widget().setParent(None)
-                import sip
                 sip.delete(child)
 
             for i in reversed(range(old_layout.count())):
diff --git a/src/calibre/gui2/comments_editor.py b/src/calibre/gui2/comments_editor.py
index 309982a51d..1d6e8097b9 100644
--- a/src/calibre/gui2/comments_editor.py
+++ b/src/calibre/gui2/comments_editor.py
@@ -8,7 +8,6 @@ __docformat__ = 'restructuredtext en'
 import re, os, json, weakref
 
 from lxml import html
-import sip
 
 from PyQt5.Qt import (QApplication, QFontInfo, QSize, QWidget, QPlainTextEdit,
     QToolBar, QVBoxLayout, QAction, QIcon, Qt, QTabWidget, QUrl, QFormLayout,
@@ -16,6 +15,10 @@ from PyQt5.Qt import (QApplication, QFontInfo, QSize, QWidget, QPlainTextEdit,
     QHBoxLayout, QKeySequence, QLineEdit, QDialogButtonBox, QPushButton,
     QCheckBox)
 from PyQt5.QtWebKitWidgets import QWebView, QWebPage
+try:
+    from PyQt5 import sip
+except ImportError:
+    import sip
 
 from calibre.ebooks.chardet import xml_to_unicode
 from calibre import xml_replace_entities, prepare_string_for_xml
diff --git a/src/calibre/gui2/complete2.py b/src/calibre/gui2/complete2.py
index d352c5d9d0..c0fb7f1cb5 100644
--- a/src/calibre/gui2/complete2.py
+++ b/src/calibre/gui2/complete2.py
@@ -9,11 +9,14 @@ __docformat__ = 'restructuredtext en'
 
 import weakref
 
-import sip
 from PyQt5.Qt import (
     QLineEdit, QAbstractListModel, Qt, pyqtSignal, QObject, QKeySequence,
     QApplication, QListView, QPoint, QModelIndex, QFont, QFontInfo,
     QStyleOptionComboBox, QStyle, QComboBox, QTimer)
+try:
+    from PyQt5 import sip
+except ImportError:
+    import sip
 
 from calibre.constants import isosx, get_osx_version
 from calibre.utils.icu import sort_key, primary_startswith, primary_contains
@@ -155,8 +158,7 @@ class Completer(QListView):  # {{{
         if widget is None:
             return
         screen = QApplication.desktop().availableGeometry(widget)
-        h = (p.sizeHintForRow(0) * min(self.max_visible_items, m.rowCount()) +
-                3) + 3
+        h = (p.sizeHintForRow(0) * min(self.max_visible_items, m.rowCount()) + 3) + 3
         hsb = p.horizontalScrollBar()
         if hsb and hsb.isVisible():
             h += hsb.sizeHint().height()
diff --git a/src/calibre/gui2/keyboard.py b/src/calibre/gui2/keyboard.py
index fa63545cfb..5079cdb8ee 100644
--- a/src/calibre/gui2/keyboard.py
+++ b/src/calibre/gui2/keyboard.py
@@ -10,11 +10,14 @@ __docformat__ = 'restructuredtext en'
 from collections import OrderedDict
 from functools import partial
 
-import sip
 from PyQt5.Qt import (QObject, QKeySequence, QAbstractItemModel, QModelIndex,
         Qt, QStyledItemDelegate, QTextDocument, QStyle, pyqtSignal, QFrame,
         QApplication, QSize, QRectF, QWidget, QTreeView,
         QGridLayout, QLabel, QRadioButton, QPushButton, QToolButton, QIcon)
+try:
+    from PyQt5 import sip
+except ImportError:
+    import sip
 
 from calibre.utils.config import JSONConfig
 from calibre.constants import DEBUG
@@ -487,8 +490,8 @@ class Editor(QFrame):  # {{{
         dup_desc = self.dup_check(sequence)
         if dup_desc is not None:
             error_dialog(self, _('Already assigned'),
-                    unicode(sequence.toString(QKeySequence.NativeText)) + ' ' +
-                    _('already assigned to') + ' ' + dup_desc, show=True)
+                    unicode(sequence.toString(QKeySequence.NativeText)) + ' ' + _(
+                        'already assigned to') + ' ' + dup_desc, show=True)
             self.clear_clicked(which=which)
 
     def dup_check(self, sequence):
diff --git a/src/calibre/gui2/metadata/pdf_covers.py b/src/calibre/gui2/metadata/pdf_covers.py
index 376dd297d9..920628259c 100644
--- a/src/calibre/gui2/metadata/pdf_covers.py
+++ b/src/calibre/gui2/metadata/pdf_covers.py
@@ -11,11 +11,14 @@ import sys, shutil, os
 from threading import Thread
 from glob import glob
 
-import sip
 from PyQt5.Qt import (
     QDialog, QApplication, QLabel, QVBoxLayout, QDialogButtonBox, Qt,
     pyqtSignal, QListWidget, QListWidgetItem, QSize, QPixmap, QStyledItemDelegate
 )
+try:
+    from PyQt5 import sip
+except ImportError:
+    import sip
 
 from calibre import as_unicode
 from calibre.ebooks.metadata.pdf import page_images
diff --git a/src/calibre/gui2/preferences/server.py b/src/calibre/gui2/preferences/server.py
index e2a5e0d460..5348c61a85 100644
--- a/src/calibre/gui2/preferences/server.py
+++ b/src/calibre/gui2/preferences/server.py
@@ -8,13 +8,16 @@ import os
 import textwrap
 import time
 
-import sip
 from PyQt5.Qt import (
     QCheckBox, QComboBox, QDialog, QDialogButtonBox, QDoubleSpinBox, QFormLayout,
     QFrame, QHBoxLayout, QIcon, QLabel, QLineEdit, QListWidget, QPlainTextEdit,
     QPushButton, QScrollArea, QSize, QSizePolicy, QSpinBox, Qt, QTabWidget, QTimer,
     QToolButton, QUrl, QVBoxLayout, QWidget, pyqtSignal
 )
+try:
+    from PyQt5 import sip
+except ImportError:
+    import sip
 
 from calibre import as_unicode
 from calibre.gui2 import (
diff --git a/src/calibre/gui2/tweak_book/file_list.py b/src/calibre/gui2/tweak_book/file_list.py
index 9331de70a9..72cce2fc46 100644
--- a/src/calibre/gui2/tweak_book/file_list.py
+++ b/src/calibre/gui2/tweak_book/file_list.py
@@ -11,13 +11,16 @@ from binascii import hexlify
 from collections import Counter, OrderedDict, defaultdict
 from functools import partial
 
-import sip
 from PyQt5.Qt import (
     QCheckBox, QDialog, QDialogButtonBox, QFont, QFormLayout, QGridLayout, QIcon,
     QInputDialog, QLabel, QLineEdit, QListWidget, QListWidgetItem, QMenu, QPainter,
     QPixmap, QRadioButton, QScrollArea, QSize, QSpinBox, QStyle, QStyledItemDelegate,
     Qt, QTimer, QTreeWidget, QTreeWidgetItem, QVBoxLayout, QWidget, pyqtSignal
 )
+try:
+    from PyQt5 import sip
+except ImportError:
+    import sip
 
 from calibre import human_readable, plugins, sanitize_file_name_unicode
 from calibre.ebooks.oeb.base import OEB_DOCS, OEB_STYLES
diff --git a/src/pyj/book_list/convert_book.pyj b/src/pyj/book_list/convert_book.pyj
index f92759d1ee..e88ae375ff 100644
--- a/src/pyj/book_list/convert_book.pyj
+++ b/src/pyj/book_list/convert_book.pyj
@@ -9,7 +9,7 @@ from ajax import ajax
 from book_list.book_details import report_load_failure
 from book_list.library_data import load_status, url_books_query
 from book_list.router import back, report_a_load_failure
-from book_list.top_bar import create_top_bar
+from book_list.top_bar import create_top_bar, set_title
 from book_list.ui import set_panel_handler
 from dom import add_extra_css, build_rule, clear
 from utils import conditional_timeout, parse_url_params
@@ -29,6 +29,7 @@ conversion_data_load_status = {'loading':True, 'ok':False, 'error_html':None, 'c
 
 def create_convert_book(container):
     conversion_data.container_id = container.getAttribute('id')
+    set_title(_('Convert: {}').format(conversion_data.title))
 
 
 # Initialization {{{
@@ -51,8 +52,10 @@ def on_data_loaded(end_type, xhr, ev):
 
 
 def fetch_conversion_data(book_id):
+    nonlocal conversion_data
     if conversion_data_load_status.current_fetch:
         conversion_data_load_status.current_fetch.abort()
+    conversion_data = None
     query = url_books_query()
     conversion_data_load_status.loading = True
     conversion_data_load_status.ok = False