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From: Terry Reedy <tjreedy@udel.edu>
Subject: Re: Deciding inheritance at instantiation?
Date: Fri, 03 Aug 2012 17:55:33 -0400
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Xref: csiph.com comp.lang.python:26456

On 8/3/2012 4:48 PM, Tobiah wrote:
> I have a bunch of classes from another library (the html helpers
> from web2py).  There are certain methods that I'd like to add to
> every one of them.  So I'd like to put those methods in a class,
> and pass the parent at the time of instantiation.  Web2py has
> a FORM class for instance.  I'd like to go:
>
>      my_element = html_factory(FORM)
>
> Then my_element would be an instance of my class, and also
> a child of FORM.
>
> I started messing with decorators, but it became difficult
> for me to visualise how to do this.

Use type(name, bases, content) for dynamic class creation.

-- 
Terry Jan Reedy