[Tutor] Adding attributes to imported class

[Michael Lange]

Hello list,

I'm trying to write a python wrapper for the tkDnD Tk extension to add drag and drop support
to Tkinter. Looking for a way to give all widgets access to the newly defined dnd methods
I came to create a subclass of Tkinter.Tk() and pass the dnd methods to Tkinter.BaseWidget() 
(all Tkinter widgets except Tk() inherit from BaseWidget()), like this:

###### file TkinterDnD.py  #########################

import Tkinter

class Tk(Tkinter.Tk):
    def __init__(self, *args, **kw):
        Tkinter.Tk.__init__(self, *args, **kw)
        self.tk.eval('package require tkdnd')

    def dnd_clearsource(self):
        '''Unregister widget as drag source.'''
        return self.tk.call('dnd', 'clearsource', self)
    Tkinter.BaseWidget.dnd_clearsource = dnd_clearsource

    < etc. >

###################################################

This is nice, because now I can simply do:

from Tkinter import *
import TkinterDnD

root = TkinterDnD.Tk()

to magically add dnd methods to all Tkinter widgets.

However, I can't help that this trick somehow reminds me of a do-it-yourself lobotomy,
so now my question, is this a common way to add new attributes to existing classes
or is it possible that this causes problems that I don't see at the moment?

Thanks in advance

Michael