[Urwid] detecting when an edit box has changed

[Eric S. Johansson]

Ian Ward wrote:
> In python you the easiest way is to override the function in a subclass. 
> eg:
> 
> class FancyEdit(urwid.Edit):
>     def set_edit_text(self, text):
>         # do things
>         urwid.Edit.set_edit_text(self, text)

okay, so it was just a vocabulary problem.  I would've called this 
delegation and method substitution (versus overloading which means you 
have multiple definitions for the same method that change based on type 
signature)