Splitting up classes between files

[Roy Smith]

I've got a top-level class, a, and a bunch of sub-classes, a1, a2, a3, etc.  To 
make it easier to manage the code, I'd like to put each in a separate file, but 
still have the user be able to import the whole bunch with a single import, i.e. 
not have to do "import a, a1, a2, a3, etc".

Can I just put "import a1, a2, a3, etc" in the bottom of my "a.py" file?  It 
seems like it should work fine, but are there any hidden gotchas?

-- 
Roy Smith <roy at popmail.med.nyu.edu>
New York University School of Medicine