os.environ.copy()['COPY_HUH'] = "not really"

[Gustavo Niemeyer]

> Under Python2.1 and earlier (back to 1.5.2):
> >>> import os
> >>> os.environ.copy()['COPY_HUH'] = "not really"
> >>> print os.environ['COPY_HUH']
> not really
> 
> Under even 2.3a0 (CVS):
> >>> import os
> >>> os.environ.copy()['COPY_HUH'] = "not really"
> >>> os.system("echo $COPY_HUH")
> not really
> 0

Here's the problem:

>>> print os.environ.__class__
os._Environ
>>> copy = os.environ.copy()
>>> print copy.__class__
os._Environ

It's not a real dictionary, but an os._Environ class. Copying it
creates instances of the same class, and that class' behavior is
to insert the item in the environment. I belive this should be
avoided in this case, returning a true dictionary from copy(). I'll
send a patch to SourceForge, if you haven't done so yet.

-- 
Gustavo Niemeyer

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