Determining the number of parameters in a lambda

Question

I am wondering if there is a way to determine (given a variable containing a lambda) the number of parameters the lambda it contains. The reason being, I wish to call a functio

Answer 1

From the documentation on callable types, the func_code attribute of functions contains a code object, and from the inspect module documentation on code objects there is a co_argcount member that contains the number of arguments (not including * or ** args).

So the best way to get this information from a lambda function (or any function) is to use func.func_code.co_argcount:

>>> foo = lambda a, b, *args, **kwargs: None
>>> foo.func_code.co_argcount
2