How to customize getattr(obj, prop) function ?

[Ben Finney]

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"Pierre" <meyer.p at gmail.com> writes:

> I don't want to use getattr(object, property, default_value) because
> I'm using external code and I don't want to modify or patch it.

You can subclass the class you want to modify, and override its behaviour.

    class ScaryExternalThing(object):
        """ The external class we don't want to modify. """

    class OurModifiedFriendlyThing(ScaryExternalThing):
        """ Class for use by our code. """

        attr_defaults = {
            'foo': "eggs",
            'bar': "beans",
        }

        def __getattr__(self, name):
            """ Method invoked when getting an unknown attribute """

            value = attr_defaults.get(name, "spam")
            return value

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_o__)                                                                  |
Ben Finney