如何将我的更改添加到python中的类？

class MyBaseClass:
    def my_method(self):
        print("Base class method")

class MySubClass(MyBaseClass):
    def my_method(self):
        super().my_method()
        print("Subclass method")

obj = MySubClass()
obj.my_method()

Base class method
Subclass method

class MyClass:
    def my_method(self):
        print("Original method")

obj = MyClass()

# 添加属性
obj.new_attribute = "New attribute"

# 添加方法
def new_method(self):
    print("New method")

MyClass.new_method = new_method

# 调用新方法和属性
print(obj.new_attribute)
obj.new_method()

New attribute
New method