diff --git a/recipes/am730.recipe b/recipes/am730.recipe
index 0d79189cbf..f5bf33d378 100644
--- a/recipes/am730.recipe
+++ b/recipes/am730.recipe
@@ -53,7 +53,7 @@ class AM730(BasicNewsRecipe):
         return self.masthead_url
 
     def getAMSectionArticles(self, sectionName,url):
-        # print sectionName
+        # print(sectionName)
         soup = self.index_to_soup(url)
         articles = []
         for aTag in soup.findAll('a',attrs={'class':'newsimglink'}):
@@ -67,7 +67,7 @@ class AM730(BasicNewsRecipe):
                 print(title)
             try:
                 if articles.index({'title':title,'url':href})>=0:
-                    # print 'already added'
+                    # print('already added')
                     continue  # already added
             except:
                 pass
diff --git a/recipes/el_pais_uy.recipe b/recipes/el_pais_uy.recipe
index 04a5e6f11c..47be554529 100644
--- a/recipes/el_pais_uy.recipe
+++ b/recipes/el_pais_uy.recipe
@@ -66,7 +66,7 @@ class General(BasicNewsRecipe):
         index = 'https://www.elpais.com.uy/impresa/'
         soup = self.index_to_soup(index)
         link_item = soup.find('a', attrs={'class': 'page-link link-module'})
-        # print link_item
+        # print(link_item)
         if link_item:
             cover_url = 'https://www.elpais.com.uy' + link_item.get('href')
         return cover_url
diff --git a/recipes/medscape.recipe b/recipes/medscape.recipe
index 098f7d54de..68cd93ebd9 100644
--- a/recipes/medscape.recipe
+++ b/recipes/medscape.recipe
@@ -56,7 +56,7 @@ class MedScrape(BasicNewsRecipe):
         # the original url is: http://www.medscape.com/viewarticle/728955?src=rss
         # the print    url is: http://www.medscape.com/viewarticle/728955_print
         print_url = url.partition('?')[0] + '_print'
-        # print 'the printable version is: ',print_url
+        # print('the printable version is: ',print_url)
         return print_url
 
     def preprocess_html(self, soup):
diff --git a/recipes/ourdailybread.recipe b/recipes/ourdailybread.recipe
index 1bbb87f984..a7a933d5b5 100644
--- a/recipes/ourdailybread.recipe
+++ b/recipes/ourdailybread.recipe
@@ -66,7 +66,7 @@ class OurDailyBread(BasicNewsRecipe):
                 div.set('class', 'calibre-inserted-psalm')
                 hr = div.makeelement('hr')
                 div.insert(0, hr)
-                # print html.tostring(div)
+                # print(html.tostring(div))
                 raw = html.tostring(root, encoding='unicode')
         return raw
 
diff --git a/recipes/presse_portal.recipe b/recipes/presse_portal.recipe
index e998e33e7c..a6940c9647 100644
--- a/recipes/presse_portal.recipe
+++ b/recipes/presse_portal.recipe
@@ -142,6 +142,6 @@ class PressePortalDE(BasicNewsRecipe):
         # and split this at the symbol '.' (if there) : ('3120111',)
         # from this take the first tuple. '3120111'
         side = (url.rpartition('/')[-1]).rsplit('.', 1)[0]
-        # print 'ConvertPrintURL from :  ' + url + '/n to ' + side
+        # print('ConvertPrintURL from :  ' + url + '/n to ' + side)
         printurl = 'http://www.presseportal.de/print/' + side + '-print.html'
         return printurl
diff --git a/recipes/the_marker.recipe b/recipes/the_marker.recipe
index 40444777e2..74ae8a0e27 100644
--- a/recipes/the_marker.recipe
+++ b/recipes/the_marker.recipe
@@ -45,5 +45,5 @@ class AdvancedUserRecipe1283848012(BasicNewsRecipe):
         rg = re.compile(re1 + re2, re.IGNORECASE | re.DOTALL)
         m = rg.search(txt)
         if m:
-            # print 'bad link'
+            # print('bad link')
             return 1
diff --git a/setup/hosting.py b/setup/hosting.py
index 2f270ad111..5750dccc0c 100644
--- a/setup/hosting.py
+++ b/setup/hosting.py
@@ -423,14 +423,14 @@ def upload_to_servers(files, version):  # {{{
     #     print('Uploading to server:', server)
     #     server = '%s.calibre-ebook.com' % server
     #     # Copy the generated index files
-    #     print ('Copying generated index')
+    #     print('Copying generated index')
     #     check_call(['rsync', '-hza', '-e', 'ssh -x', '--include', '*.html',
     #                 '--filter', '-! */', base, 'root@%s:%s' % (server, rdir)])
     #     # Copy the release files
     #     rdir = '%s%s/' % (rdir, version)
     #     for x in files:
     #         start = time.time()
-    #         print ('Uploading', x)
+    #         print('Uploading', x)
     #         for i in range(5):
     #             try:
     #                 check_call(['rsync', '-h', '-z', '--progress', '-e', 'ssh -x', x,
@@ -438,11 +438,11 @@ def upload_to_servers(files, version):  # {{{
     #             except KeyboardInterrupt:
     #                 raise SystemExit(1)
     #             except:
-    #                 print ('\nUpload failed, trying again in 30 seconds')
+    #                 print('\nUpload failed, trying again in 30 seconds')
     #                 time.sleep(30)
     #             else:
     #                 break
-    #         print ('Uploaded in', int(time.time() - start), 'seconds\n\n')
+    #         print('Uploaded in', int(time.time() - start), 'seconds\n\n')
     #
 
 
diff --git a/src/calibre/devices/kindle/bookmark.py b/src/calibre/devices/kindle/bookmark.py
index 72fdf61dea..61ddeda76d 100644
--- a/src/calibre/devices/kindle/bookmark.py
+++ b/src/calibre/devices/kindle/bookmark.py
@@ -61,11 +61,11 @@ class Bookmark:  # {{{
                 bpl = bpar_offset + 4
                 bpar_len, = unpack('>I', data[bpl:bpl+4])
                 bpar_len += 8
-                # print 'bpar_len: 0x%x' % bpar_len
+                # print('bpar_len: 0x%x' % bpar_len)
                 eo = bpar_offset + bpar_len
 
                 # Walk bookmark entries
-                # print ' --- %s --- ' % self.path
+                # print(' --- %s --- ' % self.path)
                 current_entry = 1
                 sig = data[eo:eo+4]
                 previous_block = None
@@ -80,7 +80,7 @@ class Bookmark:  # {{{
                         current_block = 'data_header'
                         # entry_type = "data_header"
                         location, = unpack('>I', data[eo+0x34:eo+0x38])
-                        # print 'data_header location: %d' % location
+                        # print('data_header location: %d' % location)
                     else:
                         current_block = 'text_block'
                         if previous_block == 'empty_data':
@@ -112,11 +112,11 @@ class Bookmark:  # {{{
                         start, = unpack('>I', data[eo+8:eo+12])
                         user_notes[start] = user_notes[end_loc]
                         '''
-                        print " %s: swapping 0x%x (%d) to 0x%x (%d)" % (user_notes[end_loc]['type'],
+                        print(" %s: swapping 0x%x (%d) to 0x%x (%d)" % (user_notes[end_loc]['type'],
                                                                     end_loc,
                                                                     end_loc/MAGIC_MOBI_CONSTANT + 1,
                                                                     start,
-                                                                    start//MAGIC_MOBI_CONSTANT + 1)
+                                                                    start//MAGIC_MOBI_CONSTANT + 1))
                         '''
                         user_notes[start]['displayed_location'] = start // MAGIC_MOBI_CONSTANT + 1
                         user_notes.pop(end_loc)
@@ -125,7 +125,7 @@ class Bookmark:  # {{{
                         # be the same - cheat by nudging -1
                         # Skip bookmark for last_read_location
                         if end_loc != self.last_read:
-                            # print ' adding Bookmark at 0x%x (%d)' % (end_loc, end_loc/MAGIC_MOBI_CONSTANT + 1)
+                            # print(' adding Bookmark at 0x%x (%d)' % (end_loc, end_loc/MAGIC_MOBI_CONSTANT + 1))
                             displayed_location = end_loc // MAGIC_MOBI_CONSTANT + 1
                             user_notes[end_loc - 1] = dict(id=self.id,
                                                            displayed_location=displayed_location,
diff --git a/src/calibre/devices/kobo/bookmark.py b/src/calibre/devices/kobo/bookmark.py
index e7739ae3f5..a2f164d9f4 100644
--- a/src/calibre/devices/kobo/bookmark.py
+++ b/src/calibre/devices/kobo/bookmark.py
@@ -149,7 +149,7 @@ class Bookmark:  # {{{
         for row in cursor:
             self.last_read = row['DateLastRead']
             self.percent_read = 100 if (row['ReadStatus'] == 2) else row['___PercentRead']
-            # print row[1]
+            # print(row[1])
         cursor.close()
 
 #                self.last_read_location = self.last_read - self.pdf_page_offset
diff --git a/src/calibre/devices/kobo/driver.py b/src/calibre/devices/kobo/driver.py
index fdfa3ea679..17116df386 100644
--- a/src/calibre/devices/kobo/driver.py
+++ b/src/calibre/devices/kobo/driver.py
@@ -321,7 +321,7 @@ class KOBO(USBMS):
                     playlist_map[lpath].append('Recommendation')
 
                 path = self.normalize_path(path)
-                # print 'Normalized FileName: ' + path
+                # print('Normalized FileName: ' + path)
 
                 idx = bl_cache.get(lpath, None)
                 if idx is not None:
@@ -332,7 +332,7 @@ class KOBO(USBMS):
                             # Try the Touch version if the image does not exist
                             imagename = self.normalize_path(self._main_prefix + KOBO_ROOT_DIR_NAME + '/images/' + ImageID + ' - N3_LIBRARY_FULL.parsed')
 
-                        # print 'Image name Normalized: ' + imagename
+                        # print('Image name Normalized: ' + imagename)
                         if not os.path.exists(imagename):
                             debug_print('Strange - The image name does not exist - title: ', title)
                         if imagename is not None:
@@ -340,7 +340,7 @@ class KOBO(USBMS):
                     if (ContentType != '6' and MimeType != 'Shortcover'):
                         if os.path.exists(self.normalize_path(os.path.join(prefix, lpath))):
                             if self.update_metadata_item(bl[idx]):
-                                # print 'update_metadata_item returned true'
+                                # print('update_metadata_item returned true')
                                 changed = True
                         else:
                             debug_print('    Strange:  The file: ', prefix, lpath, ' does not exist!')
@@ -364,7 +364,7 @@ class KOBO(USBMS):
                                         'mime: ', mime, 'date: ', date, 'ContentType: ', ContentType, 'ImageID: ', ImageID)
                             raise
 
-                    # print 'Update booklist'
+                    # print('Update booklist')
                     book.device_collections = playlist_map.get(lpath,[])  # if lpath in playlist_map else []
 
                     if bl.add_book(book, replace_metadata=False):
@@ -452,8 +452,8 @@ class KOBO(USBMS):
                 need_sync = True
                 del bl[idx]
 
-        # print 'count found in cache: %d, count of files in metadata: %d, need_sync: %s' % \
-        #      (len(bl_cache), len(bl), need_sync)
+        # print('count found in cache: %d, count of files in metadata: %d, need_sync: %s' % \
+        #      (len(bl_cache), len(bl), need_sync))
         if need_sync:  # self.count_found_in_bl != len(bl) or need_sync:
             if oncard == 'cardb':
                 self.sync_booklists((None, None, bl))
@@ -551,7 +551,7 @@ class KOBO(USBMS):
                 fpath = self.normalize_path(fpath)
 
                 if os.path.exists(fpath):
-                    # print 'Image File Exists: ' + fpath
+                    # print('Image File Exists: ' + fpath)
                     os.unlink(fpath)
 
     def delete_books(self, paths, end_session=True):
@@ -561,33 +561,33 @@ class KOBO(USBMS):
         for i, path in enumerate(paths):
             self.report_progress((i+1) / float(len(paths)), _('Removing books from device...'))
             path = self.normalize_path(path)
-            # print 'Delete file normalized path: ' + path
+            # print('Delete file normalized path: ' + path)
             extension =  os.path.splitext(path)[1]
             ContentType = self.get_content_type_from_extension(extension) if extension else self.get_content_type_from_path(path)
 
             ContentID = self.contentid_from_path(path, ContentType)
 
             ImageID = self.delete_via_sql(ContentID, ContentType)
-            # print ' We would now delete the Images for' + ImageID
+            # print(' We would now delete the Images for' + ImageID)
             self.delete_images(ImageID, path)
 
             if os.path.exists(path):
                 # Delete the ebook
-                # print 'Delete the ebook: ' + path
+                # print('Delete the ebook: ' + path)
                 os.unlink(path)
 
                 filepath = os.path.splitext(path)[0]
                 for ext in self.DELETE_EXTS:
                     if os.path.exists(filepath + ext):
-                        # print 'Filename: ' + filename
+                        # print('Filename: ' + filename)
                         os.unlink(filepath + ext)
                     if os.path.exists(path + ext):
-                        # print 'Filename: ' + filename
+                        # print('Filename: ' + filename)
                         os.unlink(path + ext)
 
                 if self.SUPPORTS_SUB_DIRS:
                     try:
-                        # print 'removed'
+                        # print('removed')
                         os.removedirs(os.path.dirname(path))
                     except Exception:
                         pass
@@ -601,9 +601,9 @@ class KOBO(USBMS):
             self.report_progress((i+1) / float(len(paths)), _('Removing books from device metadata listing...'))
             for bl in booklists:
                 for book in bl:
-                    # print 'Book Path: ' + book.path
+                    # print('Book Path: ' + book.path)
                     if path.endswith(book.path):
-                        # print '    Remove: ' + book.path
+                        # print('    Remove: ' + book.path)
                         bl.remove_book(book)
         self.report_progress(1.0, _('Removing books from device metadata listing...'))
 
@@ -634,12 +634,12 @@ class KOBO(USBMS):
                 prints('in add_books_to_metadata. Prefix is None!', path,
                         self._main_prefix)
                 continue
-            # print 'Add book to metadata: '
-            # print 'prefix: ' + prefix
+            # print('Add book to metadata: ')
+            # print('prefix: ' + prefix)
             lpath = path.partition(prefix)[2]
             if lpath.startswith('/') or lpath.startswith('\\'):
                 lpath = lpath[1:]
-            # print 'path: ' + lpath
+            # print('path: ' + lpath)
             book = self.book_class(prefix, lpath, info.title, other=info)
             if book.size is None or book.size == 0:
                 book.size = os.stat(self.normalize_path(path)).st_size
@@ -686,13 +686,13 @@ class KOBO(USBMS):
     def get_content_type_from_extension(self, extension):
         if extension == '.kobo':
             # Kobo books do not have book files.  They do have some images though
-            # print 'kobo book'
+            # print('kobo book')
             ContentType = 6
         elif extension == '.pdf' or extension == '.epub':
-            # print 'ePub or pdf'
+            # print('ePub or pdf')
             ContentType = 16
         elif extension == '.rtf' or extension == '.txt' or extension == '.htm' or extension == '.html':
-            # print 'txt'
+            # print('txt')
             if self.fwversion == (1,0) or self.fwversion == (1,4) or self.fwversion == (1,7,4):
                 ContentType = 999
             else:
@@ -708,14 +708,14 @@ class KOBO(USBMS):
             print('path from_contentid cardb')
         elif oncard == 'carda':
             path = path.replace('file:///mnt/sd/', self._card_a_prefix)
-            # print 'SD Card: ' + path
+            # print('SD Card: ' + path)
         else:
             if ContentType == '6' and MimeType == 'Shortcover':
                 # This is a hack as the kobo files do not exist
                 # but the path is required to make a unique id
                 # for calibre's reference
                 path = self._main_prefix + path + '.kobo'
-                # print 'Path: ' + path
+                # print('Path: ' + path)
             elif (ContentType == '6' or ContentType == '10') and (
                 MimeType == 'application/x-kobo-epub+zip' or (
                 MimeType == 'application/epub+zip' and self.isTolinoDevice())
@@ -724,12 +724,12 @@ class KOBO(USBMS):
                     path = self._main_prefix + path.replace('file:///mnt/onboard/', '')
                 else:
                     path = self._main_prefix + KOBO_ROOT_DIR_NAME + '/kepub/' + path
-                # print 'Internal: ' + path
+                # print('Internal: ' + path)
             else:
                 # if path.startswith('file:///mnt/onboard/'):
                 path = path.replace('file:///mnt/onboard/', self._main_prefix)
                 path = path.replace('/mnt/onboard/', self._main_prefix)
-                # print 'Internal: ' + path
+                # print('Internal: ' + path)
 
         return path
 
@@ -1820,7 +1820,7 @@ class KOBOTOUCH(KOBO):
                     debug_print('KoboTouch:update_booklist - playlist_map=', playlist_map)
 
                 path = self.normalize_path(path)
-                # print 'Normalized FileName: ' + path
+                # print('Normalized FileName: ' + path)
 
                 # Collect the Kobo metadata
                 authors_list = [a.strip() for a in authors.split('&')] if authors is not None else [_('Unknown')]
@@ -1929,7 +1929,7 @@ class KOBOTOUCH(KOBO):
                         debug_print('    bookshelves:', bookshelves)
                         debug_print('    kobo_collections:', kobo_collections)
 
-                    # print 'Update booklist'
+                    # print('Update booklist')
                     book.device_collections = playlist_map.get(lpath,[])  # if lpath in playlist_map else []
                     book.current_shelves    = bookshelves
                     book.kobo_collections   = kobo_collections
@@ -2144,8 +2144,8 @@ class KOBOTOUCH(KOBO):
                 else:
                     debug_print("KoboTouch:books - Book in mtadata.calibre, on file system but not database - bl[idx].title:'%s'"%bl[idx].title)
 
-        # print 'count found in cache: %d, count of files in metadata: %d, need_sync: %s' % \
-        #      (len(bl_cache), len(bl), need_sync)
+        # print('count found in cache: %d, count of files in metadata: %d, need_sync: %s' % \
+        #      (len(bl_cache), len(bl), need_sync))
         # Bypassing the KOBO sync_booklists as that does things we don't need to do
         # Also forcing sync to see if this solves issues with updating shelves and matching books.
         if need_sync or True:  # self.count_found_in_bl != len(bl) or need_sync:
@@ -2208,7 +2208,7 @@ class KOBOTOUCH(KOBO):
                 path = path.replace('file:///mnt/onboard/', self._main_prefix)
                 path = path.replace('file:///mnt/sd/', self._card_a_prefix)
                 path = path.replace('/mnt/onboard/', self._main_prefix)
-                # print 'Internal: ' + path
+                # print('Internal: ' + path)
 
         return path
 
diff --git a/src/calibre/devices/usbms/driver.py b/src/calibre/devices/usbms/driver.py
index 20ff03b326..1dba28aa3b 100644
--- a/src/calibre/devices/usbms/driver.py
+++ b/src/calibre/devices/usbms/driver.py
@@ -247,7 +247,7 @@ class USBMS(CLI, Device):
                     if idx is not None:
                         bl_cache[lpath] = None
                         if self.update_metadata_item(bl[idx]):
-                            # print 'update_metadata_item returned true'
+                            # print('update_metadata_item returned true')
                             changed = True
                     else:
                         if bl.add_book(self.book_from_path(prefix, lpath),
diff --git a/src/calibre/ebooks/chm/reader.py b/src/calibre/ebooks/chm/reader.py
index 2d6607eddc..4bf7b2d4e0 100644
--- a/src/calibre/ebooks/chm/reader.py
+++ b/src/calibre/ebooks/chm/reader.py
@@ -141,14 +141,14 @@ class CHMReader(CHMFile):
             else:
                 frag = None
             name = self._deentity(li.object('param', {'name': 'Name'})[0]['value'])
-            # print '========>', name
+            # print('========>', name)
             toc.add_item(href, frag, name, play_order=self._playorder)
             self._playorder += 1
             if li.ul:
                 child = self._parse_toc(li.ul)
                 child.parent = toc
                 toc.append(child)
-        # print toc
+        # print(toc)
         return toc
 
     def ResolveObject(self, path):
diff --git a/src/calibre/ebooks/conversion/utils.py b/src/calibre/ebooks/conversion/utils.py
index 28184f8330..d31e601dc0 100644
--- a/src/calibre/ebooks/conversion/utils.py
+++ b/src/calibre/ebooks/conversion/utils.py
@@ -628,7 +628,7 @@ class HeuristicProcessor:
     def check_paragraph(self, content):
         content = re.sub('\\s*</?span[^>]*>\\s*', '', content)
         if re.match('.*["\'.!?:]$', content):
-            # print 'detected this as a paragraph'
+            # print('detected this as a paragraph')
             return True
         else:
             return False
@@ -641,9 +641,9 @@ class HeuristicProcessor:
         html = re.sub('</?a[^>]*>', '', html)
 
         def convert_styles(match):
-            # print 'raw styles are: '+match.group('styles')
+            # print('raw styles are: '+match.group('styles'))
             content = match.group('content')
-            # print 'raw content is: '+match.group('content')
+            # print('raw content is: '+match.group('content'))
             image = match.group('image')
 
             is_paragraph = False
@@ -668,12 +668,12 @@ class HeuristicProcessor:
             else:
                 styles = match.group('styles').split(';')
                 is_paragraph = self.check_paragraph(content)
-                # print 'styles for this line are: '+str(styles)
+                # print('styles for this line are: '+str(styles))
                 split_styles = []
                 for style in styles:
-                    # print 'style is: '+str(style)
+                    # print('style is: '+str(style))
                     newstyle = style.split(':')
-                    # print 'newstyle is: '+str(newstyle)
+                    # print('newstyle is: '+str(newstyle))
                     split_styles.append(newstyle)
                 styles = split_styles
                 for style, setting in styles:
@@ -710,18 +710,18 @@ class HeuristicProcessor:
                             self.log.debug('padding bottom is: ' + str(setting[2]))
                             self.log.debug('padding left is: ' +str(setting[3]))
 
-                # print 'text-align is: '+str(text_align)
-                # print '\n***\nline is:\n     '+str(match.group(0))+'\n'
+                # print('text-align is: '+str(text_align))
+                # print('\n***\nline is:\n     '+str(match.group(0))+'\n')
                 if debugabby:
-                    # print 'this line is a paragraph = '+str(is_paragraph)+', previous line was '+str(self.previous_was_paragraph)
+                    # print('this line is a paragraph = '+str(is_paragraph)+', previous line was '+str(self.previous_was_paragraph))
                     self.log.debug('styles for this line were:', styles)
                     self.log.debug('newline is:')
                     self.log.debug(blockquote_open_loop+blockquote_close_loop+
                             paragraph_before+'<p style="'+text_indent+text_align+
                             '">'+content+'</p>'+paragraph_after+'\n\n\n\n\n')
-                # print 'is_paragraph is '+str(is_paragraph)+', previous_was_paragraph is '+str(self.previous_was_paragraph)
+                # print('is_paragraph is '+str(is_paragraph)+', previous_was_paragraph is '+str(self.previous_was_paragraph))
                 self.previous_was_paragraph = is_paragraph
-                # print 'previous_was_paragraph is now set to '+str(self.previous_was_paragraph)+'\n\n\n'
+                # print('previous_was_paragraph is now set to '+str(self.previous_was_paragraph)+'\n\n\n')
                 return blockquote_open_loop+blockquote_close_loop+paragraph_before+'<p style="'+text_indent+text_align+'">'+content+'</p>'+paragraph_after
 
         html = abbyy_line.sub(convert_styles, html)
@@ -772,7 +772,7 @@ class HeuristicProcessor:
             self.line_close = '\\s*(</[ibu][^>]*>\\s*)?</(?P=outer)>'
 
         # ADE doesn't render <br />, change to empty paragraphs
-        # html = re.sub('<br[^>]*>', u'<p>\u00a0</p>', html)
+        # html = re.sub('<br[^>]*>', '<p>\u00a0</p>', html)
 
         # Determine whether the document uses interleaved blank lines
         self.blanks_between_paragraphs = self.analyze_blanks(html)
diff --git a/src/calibre/ebooks/djvu/djvu.py b/src/calibre/ebooks/djvu/djvu.py
index df029e5de9..a071517983 100644
--- a/src/calibre/ebooks/djvu/djvu.py
+++ b/src/calibre/ebooks/djvu/djvu.py
@@ -37,7 +37,7 @@ class DjvuChunk:
         self.dataend = pos + self.size - (8 if inclheader else 0)
         if self.type == b'FORM':
             oldpos, pos = pos, pos+4
-            # print oldpos, pos
+            # print(oldpos, pos)
             self.subtype = buf[oldpos:pos]
             # self.headersize += 4
         self.datastart = pos
diff --git a/src/calibre/ebooks/lrf/pylrs/pylrf.py b/src/calibre/ebooks/lrf/pylrs/pylrf.py
index 4d23412d62..6a5e10a612 100644
--- a/src/calibre/ebooks/lrf/pylrs/pylrf.py
+++ b/src/calibre/ebooks/lrf/pylrs/pylrf.py
@@ -397,7 +397,7 @@ class LrfTag:
         if p is None:
             return
 
-        # print '   Writing tag', self.name
+        # print('   Writing tag', self.name)
         for f in self.format:
             if isinstance(f, dict):
                 p = f[p]
@@ -565,7 +565,7 @@ class LrfObject:
                 dotscode)))
 
     def write(self, lrf, encoding=None):
-        # print 'Writing object', self.name
+        # print('Writing object', self.name)
         LrfTag('ObjectStart', (self.objId, self.type)).write(lrf)
 
         for tag in self.tags:
diff --git a/src/calibre/ebooks/lrf/pylrs/pylrs.py b/src/calibre/ebooks/lrf/pylrs/pylrs.py
index d045936465..4594295730 100644
--- a/src/calibre/ebooks/lrf/pylrs/pylrs.py
+++ b/src/calibre/ebooks/lrf/pylrs/pylrs.py
@@ -1344,7 +1344,7 @@ class Page(LrsObject, LrsContainer):
             if hasattr(content, 'getReferencedObjIds'):
                 pageContent.update(content.getReferencedObjIds())
 
-        # print 'page contents:', pageContent
+        # print('page contents:', pageContent)
         # ObjectList not needed and causes slowdown in SONY LRF renderer
         # p.appendLrfTag(LrfTag("ObjectList", pageContent))
         p.appendLrfTag(LrfTag('Link', self.pageStyle.objId))
@@ -1620,7 +1620,7 @@ class Button(LrsObject, LrsContainer):
 
     def toLrf(self, lrfWriter):
         (refobj, refpage) = self.findJumpToRefs()
-        # print 'Button writing JumpTo refobj=', jumpto.refobj, ', and refpage=', jumpto.refpage
+        # print('Button writing JumpTo refobj=', jumpto.refobj, ', and refpage=', jumpto.refpage)
         button = LrfObject('Button', self.objId)
         button.appendLrfTag(LrfTag('buttonflags', 0x10))  # pushbutton
         button.appendLrfTag(LrfTag('PushButtonStart'))
diff --git a/src/calibre/ebooks/metadata/book/render.py b/src/calibre/ebooks/metadata/book/render.py
index b2e06ad14b..6781ab3f94 100644
--- a/src/calibre/ebooks/metadata/book/render.py
+++ b/src/calibre/ebooks/metadata/book/render.py
@@ -439,7 +439,7 @@ def mi_to_html(
 
     ans = ['<tr id="%s" class="%s">%s</tr>'%(fieldl.replace('#', '_'),
         classname(fieldl), html) for fieldl, html in ans]
-    # print '\n'.join(ans)
+    # print('\n'.join(ans))
     direction = 'rtl' if rtl else 'ltr'
     rans = f'<table class="fields" style="direction: {direction}; '
     if not for_qt:
diff --git a/src/calibre/ebooks/metadata/topaz.py b/src/calibre/ebooks/metadata/topaz.py
index 8973712fc4..e18218eaba 100644
--- a/src/calibre/ebooks/metadata/topaz.py
+++ b/src/calibre/ebooks/metadata/topaz.py
@@ -281,7 +281,7 @@ class MetadataUpdater:
         offset += 1
         self.md_header['num_recs'] = ord(self.data[offset:offset+1])
         offset += 1
-        # print 'self.md_header: %s' % self.md_header
+        # print('self.md_header: %s' % self.md_header)
 
         self.metadata = {}
         self.md_seq = []
diff --git a/src/calibre/ebooks/mobi/reader/headers.py b/src/calibre/ebooks/mobi/reader/headers.py
index 9f0021cc43..0f694eb9ff 100644
--- a/src/calibre/ebooks/mobi/reader/headers.py
+++ b/src/calibre/ebooks/mobi/reader/headers.py
@@ -108,7 +108,7 @@ class EXTHHeader:  # {{{
                 except Exception:
                     pass
             # else:
-            #    print 'unknown record', idx, repr(content)
+            #    print('unknown record', idx, repr(content))
         if title:
             self.mi.title = replace_entities(clean_xml_chars(clean_ascii_chars(title)))
 
@@ -184,7 +184,7 @@ class EXTHHeader:  # {{{
             if self.kf8_header == NULL_INDEX:
                 self.kf8_header = None
         # else:
-        #    print 'unhandled metadata record', idx, repr(content)
+        #    print('unhandled metadata record', idx, repr(content))
 # }}}
 
 
diff --git a/src/calibre/ebooks/rtf2xml/hex_2_utf8.py b/src/calibre/ebooks/rtf2xml/hex_2_utf8.py
index 0c0f68fe9b..87aba7072c 100644
--- a/src/calibre/ebooks/rtf2xml/hex_2_utf8.py
+++ b/src/calibre/ebooks/rtf2xml/hex_2_utf8.py
@@ -188,7 +188,7 @@ class Hex2Utf8:
             self.__dingbats_dict.update(ms_dingbats_dict)
         # load dictionary for caps, and make a string for the replacement
         self.__caps_uni_dict = char_map_obj.get_char_map(map='caps_uni')
-        # # print self.__caps_uni_dict
+        # # print(self.__caps_uni_dict)
         # don't think I'll need this
         # keys = self.__caps_uni_dict.keys()
         # self.__caps_uni_replace = '|'.join(keys)
@@ -478,7 +478,7 @@ class Hex2Utf8:
             if in caps, convert. Otherwise, print out.
         '''
         text = line[17:-1]
-        # print line
+        # print(line)
         if self.__current_dict_name in ('Symbol', 'Wingdings', 'Zapf Dingbats'):
             the_string = ''
             for letter in text:
@@ -494,7 +494,7 @@ class Hex2Utf8:
                 else:
                     the_string += converted
             self.__write_obj.write('tx<nu<__________<%s\n' % the_string)
-            # print the_string
+            # print(the_string)
         else:
             if self.__caps_list[-1] == 'true' \
                 and self.__convert_caps\
diff --git a/src/calibre/ebooks/rtf2xml/options_trem.py b/src/calibre/ebooks/rtf2xml/options_trem.py
index 2c33d722b3..029666c438 100644
--- a/src/calibre/ebooks/rtf2xml/options_trem.py
+++ b/src/calibre/ebooks/rtf2xml/options_trem.py
@@ -34,15 +34,15 @@ class ParseOptions:
     def __init__(self, system_string, options_dict):
         self.__system_string = system_string[1:]
         long_list  = self.__make_long_list_func(options_dict)
-        # # print long_list
+        # # print(long_list)
         short_list = self.__make_short_list_func(options_dict)
-        # # print short_list
+        # # print(short_list)
         self.__legal_options = long_list + short_list
-        # # print self.__legal_options
+        # # print(self.__legal_options)
         self.__short_long_dict = self.__make_short_long_dict_func(options_dict)
-        # # print self.__short_long_dict
+        # # print(self.__short_long_dict)
         self.__opt_with_args = self.__make_options_with_arg_list(options_dict)
-        # # print self.__opt_with_args
+        # # print(self.__opt_with_args)
         self.__options_okay = 1
 
     def __make_long_list_func(self, options_dict):
@@ -256,16 +256,16 @@ class ParseOptions:
 
     def parse_options(self):
         self.__system_string = self.__sub_short_with_long()
-        # # print 'subbed list is  %s' % self.__system_string
+        # # print('subbed list is  %s' % self.__system_string)
         self.__system_string = self.__pair_arg_with_option()
-        # # print 'list with pairing is %s' % self.__system_string
+        # # print('list with pairing is %s' % self.__system_string)
         options, arguments  = self.__get_just_options()
-        # # print 'options are %s ' % options
-        # # print 'arguments are %s ' % arguments
+        # # print('options are %s ' % options)
+        # # print('arguments are %s ' % arguments)
         self.__is_legal_option_func()
         if self.__options_okay:
             options_dict = self.__make_options_dict(options)
-            # # print options_dict
+            # # print(options_dict)
             return options_dict, arguments
         else:
             return 0,0
diff --git a/src/calibre/ebooks/rtf2xml/table.py b/src/calibre/ebooks/rtf2xml/table.py
index 91bc6b7102..9aa8ec6ec1 100644
--- a/src/calibre/ebooks/rtf2xml/table.py
+++ b/src/calibre/ebooks/rtf2xml/table.py
@@ -552,7 +552,7 @@ class Table:
             line = line_to_read
             self.__token_info = line[:16]
             action = self.__state_dict.get(self.__state[-1])
-            # print self.__state[-1]
+            # print(self.__state[-1])
             if action is None:
                 sys.stderr.write('No matching state in module table.py\n')
                 sys.stderr.write(self.__state[-1] + '\n')
diff --git a/src/calibre/ebooks/rtf2xml/tokenize.py b/src/calibre/ebooks/rtf2xml/tokenize.py
index fbdd1ebad3..ba204196b1 100644
--- a/src/calibre/ebooks/rtf2xml/tokenize.py
+++ b/src/calibre/ebooks/rtf2xml/tokenize.py
@@ -204,7 +204,7 @@ class Tokenize:
 # import sys
 # def main(args=sys.argv):
     # if len(args) < 2:
-        # print 'No file'
+        # print('No file')
         # return
     # file = 'data_tokens.txt'
     # if len(args) == 3:
diff --git a/src/calibre/gui2/comments_editor.py b/src/calibre/gui2/comments_editor.py
index 015ed28e18..e970df3f4b 100644
--- a/src/calibre/gui2/comments_editor.py
+++ b/src/calibre/gui2/comments_editor.py
@@ -1521,8 +1521,8 @@ class Editor(QWidget):  # {{{
         self.editor.html = v
 
     def change_tab(self, index):
-        # print 'reloading:', (index and self.wyswyg_dirty) or (not index and
-        #        self.source_dirty)
+        # print('reloading:', (index and self.wyswyg_dirty) or (not index and
+        #        self.source_dirty))
         if index == 1:  # changing to code view
             if self.wyswyg_dirty:
                 self.code_edit.setPlainText(self.editor.html)
@@ -1598,4 +1598,4 @@ if __name__ == '__main__':
     i = 'file:///home/kovid/work/calibre/resources/images/'
     w.html = f'<p>Testing <img src="{i}/donate.png"> img and another <img src="{i}/lt.png">file</p>'
     app.exec()
-    # print w.html
+    # print(w.html)
diff --git a/src/calibre/gui2/device_drivers/mtp_folder_browser.py b/src/calibre/gui2/device_drivers/mtp_folder_browser.py
index d283587bf9..18054dfd04 100644
--- a/src/calibre/gui2/device_drivers/mtp_folder_browser.py
+++ b/src/calibre/gui2/device_drivers/mtp_folder_browser.py
@@ -243,4 +243,4 @@ def ignored_folders():
 
 if __name__ == '__main__':
     print(browse())
-    # print ('Ignored:', ignored_folders())
+    # print('Ignored:', ignored_folders())
diff --git a/src/calibre/gui2/markdown_syntax_highlighter.py b/src/calibre/gui2/markdown_syntax_highlighter.py
index 0d4cd071b2..31dc16e025 100644
--- a/src/calibre/gui2/markdown_syntax_highlighter.py
+++ b/src/calibre/gui2/markdown_syntax_highlighter.py
@@ -186,7 +186,7 @@ class MarkdownHighlighter(QSyntaxHighlighter):
             prev = prevBlock.text()
             prevAscii = str(prev.replace('\u2029','\n'))
             if self.offset == 0 and prevAscii.strip():
-                #print 'Its a header'
+                #print('Its a header')
                 prevCursor.select(QTextCursor.SelectionType.LineUnderCursor)
                 #prevCursor.setCharFormat(self.MARKDOWN_KWS_FORMAT['Header'])
                 formatRange = QTextLayout.FormatRange()
diff --git a/src/calibre/gui2/tag_browser/model.py b/src/calibre/gui2/tag_browser/model.py
index 3622e34b8c..1dffddce40 100644
--- a/src/calibre/gui2/tag_browser/model.py
+++ b/src/calibre/gui2/tag_browser/model.py
@@ -581,7 +581,7 @@ class TagsModel(QAbstractItemModel):  # {{{
             traceback.print_stack()
             return
         # traceback.print_stack()
-        # print ()
+        # print()
         self._build_in_progress = True
         self.beginResetModel()
         self._run_rebuild(state_map=state_map)
@@ -1284,7 +1284,7 @@ class TagsModel(QAbstractItemModel):  # {{{
         self.convert_requested.emit(book_ids, fmt)
 
     def handle_drop(self, on_node, ids):
-        # print 'Dropped ids:', ids, on_node.tag
+        # print('Dropped ids:', ids, on_node.tag)
         key = on_node.tag.category
         if key == 'formats':
             self.handle_drop_on_format(on_node.tag.name, ids)
diff --git a/src/calibre/library/caches.py b/src/calibre/library/caches.py
index eed672e9f6..afbfb5da81 100644
--- a/src/calibre/library/caches.py
+++ b/src/calibre/library/caches.py
@@ -59,7 +59,7 @@ class MetadataBackup(Thread):  # {{{
                 (id_, sequence) = self.db.get_a_dirtied_book()
                 if id_ is None:
                     continue
-                # print 'writer thread', id_, sequence
+                # print('writer thread', id_, sequence)
             except:
                 # Happens during interpreter shutdown
                 break
diff --git a/src/calibre/library/catalogs/epub_mobi_builder.py b/src/calibre/library/catalogs/epub_mobi_builder.py
index 6161d6c84d..0e0d85a46c 100644
--- a/src/calibre/library/catalogs/epub_mobi_builder.py
+++ b/src/calibre/library/catalogs/epub_mobi_builder.py
@@ -1354,7 +1354,7 @@ class CatalogBuilder:
         # massaged = re.sub("&", "&#38;", massaged)
 
         if massaged.strip() and dest:
-            # print traceback.print_stack(limit=3)
+            # print(traceback.print_stack(limit=3))
             return self.generate_short_description(massaged.strip(), dest=dest)
         else:
             return None
@@ -2032,7 +2032,7 @@ class CatalogBuilder:
         bookmarked_books = []
         for bm_book in self.bookmarked_books:
             book = self.bookmarked_books[bm_book]
-            # print 'bm_book: %s' % bm_book
+            # print('bm_book: %s' % bm_book)
             book[1]['bookmark_timestamp'] = book[0].timestamp
             try:
                 book[1]['percent_read'] = min(float(100 * book[0].last_read / book[0].book_length), 100)
@@ -2139,7 +2139,7 @@ class CatalogBuilder:
         master_genre_list = []
         for genre_tag_set in genre_list:
             for (index, genre) in enumerate(genre_tag_set):
-                # print 'genre: %s  \t  genre_tag_set[genre]: %s' % (genre, genre_tag_set[genre])
+                # print('genre: %s  \t  genre_tag_set[genre]: %s' % (genre, genre_tag_set[genre]))
 
                 # Create sorted_authors[0] = friendly, [1] = author_sort for NCX creation
                 authors = []
@@ -3396,7 +3396,7 @@ class CatalogBuilder:
             for book in self.books_by_date_range:
                 book_time = datetime.datetime(book['timestamp'].year, book['timestamp'].month, book['timestamp'].day)
                 if (today_time - book_time).days <= date_range_limit:
-                    # print 'generate_ncx_by_date_added: %s added %d days ago' % (book['title'], (today_time-book_time).days)
+                    # print('generate_ncx_by_date_added: %s added %d days ago' % (book['title'], (today_time-book_time).days))
                     current_titles_list.append(book['title'])
                 else:
                     break
@@ -3505,7 +3505,7 @@ class CatalogBuilder:
             for book in self.bookmarked_books_by_date_read:
                 bookmark_time = utcfromtimestamp(book['bookmark_timestamp'])
                 if (today_time - bookmark_time).days <= date_range_limit:
-                    # print 'generate_ncx_by_date_added: %s added %d days ago' % (book['title'], (today_time-book_time).days)
+                    # print('generate_ncx_by_date_added: %s added %d days ago' % (book['title'], (today_time-book_time).days))
                     current_titles_list.append(book['title'])
                 else:
                     break
diff --git a/src/calibre/library/database2.py b/src/calibre/library/database2.py
index 0d54712301..03925d9d72 100644
--- a/src/calibre/library/database2.py
+++ b/src/calibre/library/database2.py
@@ -839,9 +839,9 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
         '''
         with self.dirtied_lock:
             dc_sequence = self.dirtied_cache.get(book_id, None)
-            # print 'clear_dirty: check book', book_id, dc_sequence
+            # print('clear_dirty: check book', book_id, dc_sequence)
             if dc_sequence is None or sequence is None or dc_sequence == sequence:
-                # print 'needs to be cleaned'
+                # print('needs to be cleaned')
                 self.conn.execute('DELETE FROM metadata_dirtied WHERE book=?',
                         (book_id,))
                 self.conn.commit()
@@ -850,7 +850,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
                 except:
                     pass
             elif dc_sequence is not None:
-                # print 'book needs to be done again'
+                # print('book needs to be done again')
                 pass
 
     def dump_metadata(self, book_ids=None, remove_from_dirtied=True,
@@ -908,12 +908,12 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
         self.update_last_modified(book_ids)
         for book in book_ids:
             with self.dirtied_lock:
-                # print 'dirtied: check id', book
+                # print('dirtied: check id', book)
                 if book in self.dirtied_cache:
                     self.dirtied_cache[book] = self.dirtied_sequence
                     self.dirtied_sequence += 1
                     continue
-                # print 'book not already dirty'
+                # print('book not already dirty')
 
                 self.conn.execute(
                     'INSERT OR IGNORE INTO metadata_dirtied (book) VALUES (?)',
@@ -964,7 +964,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
         # thread has not done the work between the put and the get_metadata
         with self.dirtied_lock:
             sequence = self.dirtied_cache.get(idx, None)
-        # print 'get_md_for_dump', idx, sequence
+        # print('get_md_for_dump', idx, sequence)
         try:
             # While a book is being created, the path is empty. Don't bother to
             # try to write the opf, because it will go to the wrong folder.
@@ -1864,7 +1864,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
                 md.append((category, cat['rec_index'],
                            cat['is_multiple'].get('cache_to_list', None),
                            cat['datatype'] == 'composite'))
-        # print 'end phase "collection":', time.clock() - last, 'seconds'
+        # print('end phase "collection":', time.clock() - last, 'seconds')
         # last = time.clock()
 
         # Now scan every book looking for category items.
@@ -1932,7 +1932,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
                         except:
                             prints('get_categories: item', val, 'is not in', cat, 'list!')
 
-        # print 'end phase "books":', time.clock() - last, 'seconds'
+        # print('end phase "books":', time.clock() - last, 'seconds')
         # last = time.clock()
 
         # Now do news
@@ -1953,7 +1953,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
             item.set_all(c=r[2], rt=r[2]*r[3], rc=r[2], id=r[0])
             tcategories['news'][r[1]] = item
 
-        # print 'end phase "news":', time.clock() - last, 'seconds'
+        # print('end phase "news":', time.clock() - last, 'seconds')
         # last = time.clock()
 
         # Build the real category list by iterating over the temporary copy
@@ -2038,7 +2038,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
                                         use_sort_as_name=use_sort_as_name)
                                     for r in items]
 
-        # print 'end phase "tags list":', time.clock() - last, 'seconds'
+        # print('end phase "tags list":', time.clock() - last, 'seconds')
         # last = time.clock()
 
         # Needed for legacy databases that have multiple ratings that
@@ -2181,8 +2181,8 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
                 icon_map['search'] = icon_map['search']
             categories['search'] = items
 
-        # print 'last phase ran in:', time.clock() - last, 'seconds'
-        # print 'get_categories ran in:', time.clock() - start, 'seconds'
+        # print('last phase ran in:', time.clock() - last, 'seconds')
+        # print('get_categories ran in:', time.clock() - start, 'seconds')
 
         return categories
 
diff --git a/src/calibre/utils/mdns.py b/src/calibre/utils/mdns.py
index db84d4cc64..5a70e9c871 100644
--- a/src/calibre/utils/mdns.py
+++ b/src/calibre/utils/mdns.py
@@ -38,9 +38,9 @@ class AllIpAddressesGetter(Thread):
 
     def run(self):
         global _all_ip_addresses
-#        print 'sleeping'
+#        print('sleeping')
 #        time.sleep(15)
-#        print 'slept'
+#        print('slept')
         _all_ip_addresses = self.get_all_ips()
 
 
@@ -74,7 +74,7 @@ def _get_external_ip():
                     break
             except:
                 time.sleep(0.3)
-    # print 'ipaddr: %s' % ipaddr
+    # print('ipaddr: %s' % ipaddr)
     return ipaddr
 
 
diff --git a/src/calibre/web/feeds/templates.py b/src/calibre/web/feeds/templates.py
index 9e63d330e8..e4a8af5257 100644
--- a/src/calibre/web/feeds/templates.py
+++ b/src/calibre/web/feeds/templates.py
@@ -330,7 +330,7 @@ class TouchscreenFeedTemplate(Template):
         navbar_t.append(navbar_tr)
         top_navbar = navbar_t
         bottom_navbar = copy.copy(navbar_t)
-        # print '\n%s\n' % etree.tostring(navbar_t, pretty_print=True)
+        # print('\n%s\n' % etree.tostring(navbar_t, pretty_print=True))
 
         # Build the page
         head = HEAD(TITLE(feed.title))
@@ -423,6 +423,6 @@ class TouchscreenNavBarTemplate(Template):
         navbar_tr.append(TD(attrs('article_next'),link))
         navbar_t.append(navbar_tr)
         navbar.append(navbar_t)
-        # print '\n%s\n' % etree.tostring(navbar, pretty_print=True)
+        # print('\n%s\n' % etree.tostring(navbar, pretty_print=True))
 
         self.root = HTML(head, BODY(navbar))