USPS Module does not have a password field

I am new to OpenCart and cannot figure out how to get the USPS module to work. There is a field for my USPS UserName and for my zip code, but no field for my USPS password. Should there be a password field?

Version 1.5.2.1
I too am having this issue with the default USPS module.

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Authorization failure. You are not authorized to connect to this server.

Please search "usps password" and "Authorization failure. You are not authorized to connect to this server." as these have both been answered ad nauseum.

Tip for life.. always search the error you are getting.