Export/Save state of level

[asdf]

I want to import the level, change some of the loaded objects and save the level again.
Is there some kind of best practise?

If there isn't i would save all objects in some kind of XML file or (if there is some kind of "masterarray with all objects") serialise them with pickle for python.
Any suggestions regarding these ideas?

The Question is somewhat related to this question, except that i don't really care about the exported format, as long as i can import it again.