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Subject: Re: When do default parameters get their values set?
Date: Tue, 09 Dec 2014 18:07:53 -0500
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Xref: csiph.com comp.lang.python:82242

On Tue, Dec 9, 2014, at 16:18, Duncan Booth wrote:
> The default parameters are actually evaluated when the 'def' statement is 
> executed and the function object is created from the default arguments
> and 
> the previously compiled code block.

Which means that if you execute the def statement [or lambda] more than
once, you will get more than one instance of the default parameter.

>>> def f(): return (lambda x={}: x)
...
>>> f()() is f()()
False
>>> g = f()
>>> g() is g()
True