<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def rates_for_location(self, postal_code, location_deets=None):
 """Shows the sales tax rates for a given location."""

        request = self._get("rates/" + postal_code, location_deets)
        return self.responder(request)