def reverse_geocode
      do_lookup(true) do |o,rs|
        if r = rs.first
          unless r.address.nil?
            o.__send__ "#{self.class.geocoder_options[:fetched_address]}=", r.address
          end
          r.address
        end
      end
    end
def reverse_geocode
      do_lookup(true) do |o,rs|
        if r = rs.first
          unless r.address.nil?
            o.__send__ "#{self.class.geocoder_options[:fetched_address]}=", r.address
          end
          r.address
        end
      end
    end
Look up address and assign to +address+ attribute (or other as specified
 in +reverse_geocoded_by+). Returns address (string).