

class Receiver1:
    # action
    def step_left(self):
        print("Receiver1 steps left")

    def step_right(self):
        print("Receiver1 steps right")


class Receiver2:
    # action
    def step_forward(self):
        print("Receiver2 steps forward")

    def step_backward(self):
        print("Receiver2 steps backwards")
