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From: "Joseph L. Casale" <jcasale@activenetwerx.com>
Newsgroups: comp.lang.python
Subject: Re: Static caching property
Date: Mon, 21 Mar 2016 17:03:49 +0000
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Xref: csiph.com comp.lang.python:105375

> One solution is to use descriptor protocol on the class, which means
> using a metaclass. I'm not sure it's the best option, but it is an
> option.

I will look at that, I wonder if however I am not over complicating it:

class Foo:
    _bar =3D None
    @property
    def expensive(self):
        if Foo._bar is None:
            import something
            Foo._bar =3D something.expensive()
        return Foo._bar

Somewhat naive, but a test with if is pretty cheap...
Thanks Chris,
jlc