在python中，如何在类外部的普通函数中使用类的方法？

class MyClass:
    def my_method(self):
        print("This is a method of MyClass")

def my_function():
    obj = MyClass()
    obj.my_method()

my_function()

class MyClass:
    @staticmethod
    def my_method():
        print("This is a method of MyClass")

def my_function():
    MyClass.my_method()

my_function()

class MyClass:
    @classmethod
    def my_method(cls):
        print("This is a method of MyClass")

def my_function():
    MyClass.my_method()

my_function()