order = Order() order.quantity = 10 # Works

class Temperature: def __init__(self, celsius: float): self._celsius = celsius @property def celsius(self): return self._celsius @celsius.setter def celsius(self, value): if value < -273.15: raise ValueError("Below absolute zero") self._celsius = value

class A: def greet(self): print("A")

class Bird: def (self, mover, flyer): self.mover = mover self.flyer = flyer def move(self): return self.mover.move() def fly(self): return self.flyer.fly()