scripting: wait until import is finished

[Thomas Volkmann]

Hi, it's getting too late now, and I'm already in a 
"making-one-mousclick-where-I-normally-make-twenty" mode. so can someone 
please help me?
I need to batch process a couple of fbx files, but my script doesn't 
wait for the import (FBXImport()) to finish and hence doesn't find all 
the stuff it shall process.
I tried time.sleep(), but that doesn't seem to work.... any ideas?
thanks,
Thomas