class Test:
    def __init__(self, val) -> None:
        self.val = val

    def p(self):
        print(self.val)
        print(type(self.val))
        print(str(self.val))
        print(f"Hello from {self.val}")


t = Test(val=None)
t.p()

class TestTwo:
    def __init__(self, val) -> None:
        if not isinstance(val, int):
            raise OSError
        self.val = val

    def p(self):
        print(self.val)
        print(type(self.val))

t_two = TestTwo(val=True)
t_two.p()