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From: Jussi Piitulainen <jussi.piitulainen@helsinki.fi>
Newsgroups: comp.lang.python
Subject: Re: Set Operations on Dicts
Date: Mon, 08 Feb 2016 17:05:56 +0200
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Random832 writes:

> On Mon, Feb 8, 2016, at 08:32, Matt Wheeler wrote:
>> On 8 February 2016 at 12:17, Jussi Piitulainen wrote:
>> > Also, what would be the nicest current way to express a priority union
>> > of dicts?
>> >
>> > { k:(d if k in d else e)[k] for k in d.keys() | e.keys() }
>> 
>> Since Python 3.5: {**e, **d}
>
> And before that... dict(ChainMap(d, e))

New in version 3.3. Thanks, I didn't know of that either. Reading the
docs, I think for the use I had in mind, ChainMap(d, e) itself would
suffice.