Detecting arguments of a function - possible?

[Chance Ginger]

I am trying to write a tool to examine a function (I'd like it
to work with pyc files only). So here are a few questions I 
have; any pointers would be very welcome.

Can I determine the number of arguments required of a function?
Is there a way to detect is the function will throw an exception
(I don't care under what conditions just that it is possible)?

Thanks in advance...
Chas.