题解 | #禁止重复注册#

import sys



def toupper(x):
    return x.upper()

current_users = ["Niuniu","Niumei","GURR","LOLO"]
new_users = ["GurR","Niu Ke Le","LoLo","Tuo Rui Chi"]
current_users =list(map(toupper,current_users))


for x in new_users:
    if x.upper() in current_users:
        print("The user name {} has already been registered! Please change it and try again!".format(x))
    else:
        print("Congratulations, the user name {} is available!".format(x))