Behavioral/command.py

# ----------------
# Command Pattern.
# ----------------
# Encapsulate a request as an object, thereby allowing for the parameterization of clients with different requests, 
# and the queuing or logging of requests. It also allows for the support of undoable operations.

from abc import ABC, abstractmethod

class Command(ABC):
    def __init__(self, receiver):
        self.receiver = receiver

    def process(self):
        pass

class CommandImplementation(Command):
    def __init__(self, receiver):
        self.receiver = receiver

    def process(self):
        self.receiver.perform_action()


class Receiver:
    def perform_action(self):
        print('Action performed in receiver.')

class Invoker:
    def command(self, cmd):
        self.cmd = cmd

    def execute(self):
        self.cmd.process()


receiver = Receiver()
cmd = CommandImplementation(receiver)
invoker = Invoker()
invoker.command(cmd)
invoker.execute()