Logged In: YES 
user_id=2772

This is a documentation bug.  The Tk documentation says
(canvas, section "ITEM IDS AND TAGS"):
       Each  item may also have any number of tags
associated with it.  A tag
       is just a string of characters, and it may take any
form  except  that
       of  an  integer.   For example, ‘‘x123’’ is OK but
‘‘123’’ isn’t.  The
       same tag may be associated with many different items.

Furthermore, the site www.pythonware.com is a third-party
site not run by the Python developers.  The official Python
documentation
(http://docs.python.org/lib/module-Tkinter.html and 'pydoc
Tkinter') doesn't explain the syntax of an item tag anywhere
that I could see)

I recommend closing this bug and notifying pythonware.com /
Fredrik Lundh about the problem via e-mail.