[Chicago] I don't get why this works

[Randy Baxley]

That is fun.

>>> a = {}
>>> a['a'] = a[a['a']] = 'b'
>>> a
{'a': 'b', 'b': 'b'}

does indeed work the same as:

>>> a = {}
>>> a['a'] = 'b'
>>> a
{'a': 'b'}
>>> a['a']
'b'
>>> a[a['a']] = 'b'
>>> a
{'a': 'b', 'b': 'b'}


On Mon, Apr 1, 2013 at 10:24 PM, Brantley Harris <deadwisdom at gmail.com>wrote:

> > a = {}
> > a['a'] = a[a['a']] = 'b'
> {'a': 'b', 'b': 'b'}
>
> What the what?  I would think that should KeyError, but it runs fine.
>  Someone splain.
>
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