The Mapping class has a private method __update that is intended to be a class-private method using name mangling. In the init method, an empty list items_list is initialized, and the private method __update is called with an iterable argument. update Method in Mapping Class:
The update method in the Mapping class appends items from the given iterable to the items_list. Name Mangling for Private Method:
The line __update = update creates a private copy of the update method using name mangling. The mangled name is _Mapping__update. MappingSubclass Class:
The MappingSubclass class is a subclass of the Mapping class. It overrides the update method to provide a new signature while still appending items to the items_list. Creating an Instance:
An instance of MappingSubclass is created with an iterable ['a', 'b']. Accessing items_list:
The items_list of the instance is accessed and printed. The output is ['a', 'b']. Accessing Private Method Using Name Mangling:
The private method __update is accessed using name mangling (_Mapping__update) and is called with the iterable ['c', 'd']. This appends items to the items_list. Accessing items_list Again:
The items_list of the instance is accessed and printed again. The output is ['a', 'b', 'c', 'd']. Code Output:
['a', 'b']
['a', 'b', 'c', 'd']
Name mangling is used for creating a private method (__update) in the Mapping class. The MappingSubclass class overrides the update method with a new signature without breaking the init method of the base class. Access to the private method is demonstrated using name mangling (_Mapping__update). This example illustrates how name mangling can be used for a form of encapsulation in Python.