Currently the repr() for Tcl_Obj is not very useful. It exposes only Tcl type name and Tcl object address.

>>> import tkinter.ttk
>>> tv = tkinter.ttk.Treeview()
>>> tv.tag_configure('test', foreground='blue')
{}
>>> str(tv.tag_configure('test', 'foreground'))
'blue'
>>> tv.tag_configure('test', 'foreground')
<color object at 0xb70f84b8>

You need explicitly call str to get more useful information. This is awkward when Tcl object hidden deeply in tuples or other data structure, or reported in a backtrace. Actually every Tcl object can be represented as a string. I propose to expose this representation in repr(). With proposed patch the output of the last command will be: <color object: 'blue'>.