题解 | #禁止重复注册#

current_users = ['Niuniu','Niumei','GURR','LOLO']
new_users = ['GurR','Niu Ke Le','LoLo','Tuo Rui Chi']
new_users_list = []
for j in current_users:
    new_users_list.append(j.lower())
for i in new_users:
        if i.lower() in new_users_list:
            print(f"The user name {i} has already been registered! Please change it and try again! ")
        else:
            print(f"Congratulations, the user name {i} is available!")