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To: python-list@python.org
From: Christian Heimes <christian@python.org>
Subject: Re: subclassable types
Date: Fri, 22 Feb 2013 12:00:35 +0100
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Xref: csiph.com comp.lang.python:39540

Am 22.02.2013 10:35, schrieb Wolfgang Maier:
> Also: can you use introspection to find out whether a type is valid as a
> base type?

I don't think so. For CPython the information is stored in the type's
structure. When type->tp_flags & Py_TPFLAGS_BASETYPE is true then
subclassing is allowed. But I know of no way to retrieve that
information from Python code.