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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Wed, 4 Feb 2015 10:22:02 -0700
Subject: Re: pymongo and attribute dictionaries
To: Python <python-list@python.org>
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On Wed, Feb 4, 2015 at 9:50 AM, Travis Griggs <travisgriggs@gmail.com> wrot=
e:
> I really like pymongo. And I really like Python. But one thing my fingers=
 really get tired of typing is
>
> someDoc[=E2=80=98_=E2=80=99id=E2=80=99]
>
> This just does not roll of the fingers well. Too many =E2=80=9Creach for =
modifier keys=E2=80=9D in a row. I would rather use
>
> someDoc._id
>
> Googling shows that I=E2=80=99m not the first to want to do this in the g=
eneral sense (e.g. http://stackoverflow.com/questions/4984647/accessing-dic=
t-keys-like-an-attribute-in-python).
>
> Arguments aside of whether this should or shouldn=E2=80=99t be done, I wa=
nt to know how I might solve this with Python. Consider it an academic purs=
uit.
>
> The problem I have is not how to do the AttributeDictionary subclass, the=
re are plenty of those examples. The problem is that the pymongo APIs alrea=
dy return dictionaries. In a language (Smalltalk, Objective-C, Ruby) that s=
upports class extensions, that would be my first tool of choice to solve th=
is problem. I=E2=80=99d just extend Dictionary to behave the way I want and=
 be done with it. I can=E2=80=99t do that in Python though. I guess I could=
 make my own module that subclasses the relevant pymongo classes, and do su=
per() calling implementations of all of the relevant methods, coercing the =
return type. That is a maintenance headache though.
>
> What are my options, if any?

You could construct the AttributeDictionary by copying the dict
returned from pymongo. The question then is whether the copying would
be too expensive or not.

Alternately, you could just wrap the dictionaries returned by pymongo
in an object. Something like this should be all you need:

class AttrDictWrapper(object):
    def __init__(self, the_dict):
        self.__dict__ =3D the_dict

>>> d =3D AttrDictWrapper({'spam': 42, 'ham': False})
>>> d.spam
42
>>> d.ham
False