memento design pattern

memento.py

class Memento():
    
    def __init__(self, state):
        self.state = state
        print(f"I am a Memento and my state is {self.state}")

class Originator():
    
    def __init__(self):
        self._state = ""

    def get_state(self):
        return self._state

    def set_state(self, state):
        self._state = state
        print(f"New State of Originator: {self._state}")

    def get_memento(self):
        print("Providing a new memento object of current state")
        return Memento(self._state)

    def memento(self, memento):
        print(f"Returning to the state of memento {memento.state}")
        self._state = memento.state        
        
        
class CareTaker():

    def __init__(self, originator):
        self._originator = originator
        self._mementos = []

    def create(self):
        memento = self._originator.get_memento()
        self._mementos.append(memento)
        print("Total mementos in caretaker: ",len(self._mementos))

    def restore(self, index):
        print(f"Undo operation at {index} index")
        memento = self._mementos[index]
        print(memento.state)
        self._originator.memento(memento)