import inspect


def test_1():
    class FooStaticmethod:
        @staticmethod
        def __call__(cls, s, l, t):
            return t

    instance = FooStaticmethod()
    instance(1, 2, 3, 4) # Success call with 4 args

    assert list(inspect.signature(instance).parameters.keys()) == ['cls', 's', 'l', 't']


def test_2():
    class FooClassmethod:
        @classmethod
        def __call__(cls, s, l, t):
            return t

    instance = FooClassmethod()
    instance(1, 2, 3) # Success call with 4 args

    assert list(inspect.signature(instance).parameters.keys()) == ['s', 'l', 't']

def test_3():
    class FooStaticmethod:
        @staticmethod
        def __call__():
            return None

    instance = FooStaticmethod()
    instance()

    assert list(inspect.signature(instance).parameters.keys()) == []