import sys current_users=['Niuniu','Niumei','GURR','LOLO'] current_users_lower=[current_users[0].lower(),current_users[1].lower(),current_users[2].lower(),current_users[3].lower()] new_users=['GurR','Niu Ke Le','LoLo','Tuo Rui Chi'] for name in new_users: if name.lower() in current_users_l...