How to get a code for samsung sgh-a177 with AT&T?

Here is the unlocking instruction for Samsung A177 phone.you need to Switch ON your phone without your SIM Card. Compose: #7465625*638*CODE# (or *#7465625*638*CODE#).
Device should say that Network Lock Deactivated

It looks like as if you can unlock your phone by way of a code, I don't think this is a OS, so by trying this may code maybe you'll be able to unlock it by

*2767*3855#

*7465625*638*00000000*00000000 your Sim card mustbe out

Insert Sim card
*7465625*638*00000000#
Take out the battery and insert it back, if the display shows Wrong Sim, type in the new PW:
00000000.
I hope it works.