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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def address(self, street, city=None, state=None, zipcode=None, **kwargs):
        '''Geocode an address.'''
        fields = {
            'street': street,
            'city': city,
            'state': state,
            'zip': zipcode,
        }

        return self._fetch('address', fields, **kwargs)