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Date: Thu, 15 Sep 2011 12:10:58 +0100
Subject: How does a function know the docstring of its code object?
From: Arnaud Delobelle <arnodel@gmail.com>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:13317

Hi all,

You can do:

def foo():
    "foodoc"
    pass

function = type(lambda:0)
foo2 = function(foo.__code__, globals())
assert foo2.__doc__ == "foodoc"

I am wondering how the function constructor knows that foo.__code__
has a docstring.  I can see that

    foo.__code__.co_consts == ('foodoc',)

But I can't find where in foo.__code__ is stored the information that
the first constant in foo.__code__ is actually a docstring.

-- 
Arnaud