[Tutor] Check Number of Parameters Passed In

[James]

Hi All,

I'm writing a function that has optional paramters (i.e., "foo(
parameter , optionalParameter = None , optionalParameter2 = None )").

Is there some way inside of foo() that I can check to see how many
parameters have been passed in? I want to check to ensure that only
*one* optional parameter is passed in (and if more than one is passed
in, do some sort of error handling).

Thanks!
- j