emded revision control in Python application?

[duncan smith]

Hello,
       I have an application that would benefit from collaborative 
working. Over time users construct a "data environment" which is a 
number of files in JSON format contained in a few directories (in the 
future I'll probably place these in a zip so the environment is 
contained within a single file). At the moment there is one individual 
constructing the data environment, and me occasionally applying 
corrections after being e-mailed the files. But in the future there 
might be several individuals in various locations.

As a minimum requirement I need to embed some sort of version control, 
so that changes committed by one individual will be seen in the local 
environments of the others. Some of the work involves editing graphs 
which have restrictions on their structure. In this case it would be 
useful for edits to be committed / seen in real time. The users will not 
be particularly technical, so the version control will have to happen 
relatively quietly in the background.

My immediate thoughts are to (somehow) embed Mercurial or Subversion. It 
would certainly be useful to be able to revert to a previous version of 
the data environment if an individual does something silly. But I'm not 
actually convinced that this is the whole solution for collaborative 
working. Any advice regarding the embedding of a version control system 
or alternative approaches would be appreciated. I haven't tried anything 
like this before. The desktop application is written in Python (2.6) 
with a wxPython (2.8) GUI. Given the nature of the application / data 
the machines involved might be locally networked but without web access 
(if this makes a difference). TIA.

Duncan