class HauntedBus():

	def __init__(self,passengers=[]):
		self.passengers=passengers

	def pick(self,name):
		self.passengers.append(name)

	def drop(self,name):
		self.passengers.remove(name)

bus1=HauntedBus(['Alice','Bill'])
# print(bus1.passengers)
bus1.pick('Charlie')
bus1.drop('Alice')
# print(bus1.passengers)
bus2=HauntedBus()
bus2.pick('Carrie')
# print(bus2.passengers)
bus3=HauntedBus()
# print(bus3.passengers)
bus3.pick('Dave')
# print(bus3.passengers)
# print(bus2.passengers)
# print(bus3.passengers is bus2.passengers)
# print(bus1.passengers)
print(HauntedBus.__init__.__defaults__[0])