问如何在Python中保护函数不受基类的影响？

EN

import abc

class AbstractClass(metaclass=abc.ABCMeta):
    """
    Define abstract primitive operations that concrete subclasses define
    to implement steps of an algorithm.
    Implement a template method defining the skeleton of an algorithm.
    The template method calls primitive operations as well as operations
    defined in AbstractClass or those of other objects.
    """
    def template_method(self):
        self._primitive_operation_1()
        self._primitive_operation_2()
        self._primitive_operation_3()

    # Functions must be specified by subclass (i.e., subclass variant)
    @abc.abstractmethod
    def _primitive_operation_1(self):
        pass

    # Functions must be specified by subclass (i.e., subclass variant)
    @abc.abstractmethod
    def _primitive_operation_2(self):
        pass

    # Functions inherited and not modified by subclass (i.e., subclass invariant)
    def _primitive_operation_3(self):
        print ('Execute operation #3 from main class')

class ConcreteClass(AbstractClass):
    """
    Implement the primitive operations to carry out
    subclass-specificsteps of the algorithm.
    """
    def _primitive_operation_1(self):
        pass

    def _primitive_operation_2(self):
        pass

    # You can still overwrite it if you want
    def _primitive_operation_3(self):
        print ('Execute operation #3 from subclass')

def main():
    concrete_class = ConcreteClass()
    concrete_class.template_method()

if __name__ == "__main__":
    main()