Python function parameter count [duplicate]

Question

Possible Duplicate:
How to find out the arity of a method in Python

Given a python function, how do I programmatically determine the number of parameters it takes?

Answer 1

inspect is your friend in this case

>>> def testFunc(arg1, arg2, arg3, additional='test'):
...     print arg1
... 
>>> import inspect
>>> inspect.getargspec(testFunc)
ArgSpec(args=['arg1', 'arg2', 'arg3', 'additional'], varargs=None, keywords=None, defaults=('test',))
>>> 

Answer 2

From outside the function, you can use inspect.getargspec(): http://docs.python.org/library/inspect.html#inspect.getargspec