Implementing Command pattern with Python

Command pattern is a behavior design pattern, which aims to encapsulate requests as objects for parameterization according to different requests. By encapsulating a request as an object, users can use different requests to parameterize other objects (such as logging, Transaction processing processing, or queues), and support undoable operations. The following is a complete sample code for implementing Command pattern in Python: python #Command interface class Command: def execute(self): pass #Command Implementation Class class LightOnCommand(Command): def __init__(self, light): self.light = light def execute(self): self.light.on() class LightOffCommand(Command): def __init__(self, light): self.light = light def execute(self): self.light.off() #Receiver of command class Light: def on(self): Print ("The light is on") def off(self): Print ("The light is off") #Command caller class RemoteControl: def __init__(self): self.command = None def set_command(self, command): self.command = command def press_button(self): self.command.execute() #Test Code def main(): light = Light() light_on_command = LightOnCommand(light) light_off_command = LightOffCommand(light) remote_control = RemoteControl() remote_control.set_command(light_on_command) Remote_ Control. press_ Button() # Turn on the light remote_control.set_command(light_off_command) Remote_ Control. press_ Button() # Turn off the light if __name__ == "__main__": main() In the above example, the 'Command' interface defines the 'execute' method. The specific command classes' LightOnCommand 'and' LightOffCommand 'implement the' Command 'interface and encapsulate requests as objects. `The Light class, as the receiver of commands, performs the corresponding operations in the 'execute' methods of 'LightOnCommand' and 'LightOffCommand'. `The RemoteControl class serves as a command caller, using 'set'_ The command 'method sets specific commands and uses' press'_ The button 'method is used to execute commands. In this way, users can create different command implementation classes according to their needs and execute the corresponding commands by calling the 'RemoteControl' method. This achieves the goal of encapsulating, parameterizing, and revoking requests.