inspect.signature()

inspect.signature(callable, *, follow_wrapped=True)

Return a Signature object for the given callable:

>>> from inspect import signature
>>> def foo(a, *, b:int, **kwargs):
...     pass

>>> sig = signature(foo)

>>> str(sig)
'(a, *, b:int, **kwargs)'

>>> str(sig.parameters['b'])
'b:int'

>>> sig.parameters['b'].annotation
<class 'int'>

Accepts a wide range of python callables, from plain functions and classes to functools.partial() objects.

Raises ValueError if no signature can be provided, and TypeError if that type of object is not supported.