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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:18874

Máté Koch wrote:

> I'm developing an app which stores the data in file system database. The
> data in my case consists of large python objects, mostly dicts, containing
> texts and numbers. The easiest way to dump and load them would be pickle,
> but I have a problem with it: I want to keep the data in version control,
> and I would like to use it as efficiently as possible. Is it possible to
> force pickle to store the otherwise unordered (e.g. dictionary) data in a
> kind of ordered way, so that if I dump a large dict, then change 1 tiny
> thing in it and dump again, the diff of the former and the new file will
> be minimal?
> 
> If pickle is not the best choice for me, can you suggest anything else?
> (If there isn't any solution for it so far, I will write the module of
> course, but first I'd like to look around and make sure it hasn't been
> created yet.)

Have you considered json? 

http://docs.python.org/library/json.html

The encoder features a sort_keys flag which might help.