I'm not even going to list all of the issues with this command because there are too many of them, but if you were working on a version that would actually check users' IP addresses, why would you post a HIGHLY INSECURE version that allows anyone to log in as anyone? That's the biggest problem I see here.
Because this is at least the fifth time that you've posted a broken script, this is your final warning. TEST your code first, and make sure it is COMPLETE, or you will NOT be allowed to post here again.