diff --git a/src/calibre/gui2/tweak_book/__init__.py b/src/calibre/gui2/tweak_book/__init__.py
index 274fa575cd..45e80f6fe2 100644
--- a/src/calibre/gui2/tweak_book/__init__.py
+++ b/src/calibre/gui2/tweak_book/__init__.py
@@ -6,6 +6,8 @@ from __future__ import (unicode_literals, division, absolute_import,
 __license__ = 'GPL v3'
 __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'
 
+import string
+
 from calibre.utils.config import JSONConfig
 tprefs = JSONConfig('tweak_book_gui')
 
@@ -19,6 +21,10 @@ tprefs.defaults['choose_tweak_fmt'] = True
 tprefs.defaults['tweak_fmt_order'] = ['EPUB', 'AZW3']
 tprefs.defaults['update_metadata_from_calibre'] = True
 
+ucase_map = {l:string.ascii_uppercase[i] for i, l in enumerate(string.ascii_lowercase)}
+def capitalize(x):
+    return ucase_map[x[0]] + x[1:]
+
 _current_container = None
 
 def current_container():
diff --git a/src/calibre/gui2/tweak_book/editor/canvas.py b/src/calibre/gui2/tweak_book/editor/canvas.py
index a010be4c98..3a634a419f 100644
--- a/src/calibre/gui2/tweak_book/editor/canvas.py
+++ b/src/calibre/gui2/tweak_book/editor/canvas.py
@@ -6,7 +6,7 @@ from __future__ import (unicode_literals, division, absolute_import,
 __license__ = 'GPL v3'
 __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'
 
-import sys, string, weakref
+import sys, weakref
 from functools import wraps
 
 from PyQt4.Qt import (
@@ -16,6 +16,7 @@ from PyQt4.Qt import (
 from calibre import fit_image
 from calibre.constants import isosx
 from calibre.gui2 import error_dialog, pixmap_to_data
+from calibre.gui2.tweak_book import capitalize
 from calibre.utils.config_base import tweaks
 from calibre.utils.magick import Image
 from calibre.utils.magick.draw import identify_data
@@ -30,10 +31,6 @@ def painter(func):
             painter.restore()
     return ans
 
-ucase_map = {l:string.ascii_uppercase[i] for i, l in enumerate(string.ascii_lowercase)}
-def capitalize(x):
-    return ucase_map[x[0]] + x[1:]
-
 class SelectionState(object):
 
     __slots__ = ('last_press_point', 'current_mode', 'rect', 'in_selection', 'drag_corner', 'dragging', 'last_drag_pos')