iphone7 = ['lin','yao','hong','ding','qiao'] iphone8 = ['lin','xiao','hong','mao','wang'] user = [] user7 = [] user8 = [] for names in iphone7: if names in iphone8: user.append(names) else: user7.append(names) for names in iphone8: if names not in iphone7: user8.append(names) print(user) print(user7) print(user8) #user9 = user7 + user8 user7.extend(user8) print(user7) user9 = user7 print(user9)