python 定义类时，内部方法的互相调用

class MyClass:
    def __init__(self):
        pass
    def func1(self):
        # do something
        print('a')   #for example      
        self.common_func()
     def func2(self):
        # do something
        self.common_func()
         
     def common_func(self):
         pass