rename objects by projectname

Hi there,
i wanna automatically rename a null-object with the filename.
Is there a simple way to set this up, maybe in xpresso or python (i never used python bevore)?
I mean something like the token at the renderpath, just for naming an object?
I wanna have a null-object in every c4d-file based on the filename, as a starting hirachie.
That would save me a ton of time.