File "/src/erfgoedbot/categorize_images.py", line 263, in replace_default_cat_with_new_categories_in_image_text
page_text_without_base_category, new_categories, addOnly=True)
File "/src/.tox/py27/lib/python2.7/site-packages/pywikibot/textlib.py", line 1459, in replaceCategoryLinks
new_cats = categoryFormat(new, insite=site)
File "/src/.tox/py27/lib/python2.7/site-packages/pywikibot/textlib.py", line 1552, in categoryFormat
category = pywikibot.Category(category)
File "/src/.tox/py27/lib/python2.7/site-packages/pywikibot/tools/__init__.py", line 1819, in wrapper
return obj(*__args, **__kw)
File "/src/.tox/py27/lib/python2.7/site-packages/pywikibot/page/__init__.py", line 2879, in __init__
Page.__init__(self, source, title, ns=14)
File "/src/.tox/py27/lib/python2.7/site-packages/pywikibot/tools/__init__.py", line 1819, in wrapper
return obj(*__args, **__kw)
File "/src/.tox/py27/lib/python2.7/site-packages/pywikibot/page/__init__.py", line 2392, in __init__
super(Page, self).__init__(source, title, ns)
File "/src/.tox/py27/lib/python2.7/site-packages/pywikibot/page/__init__.py", line 221, in __init__
.format(type(source), source))
Error: Invalid argument type '<type 'str'>' in Page initializer: B
```