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 alr...