docs: def _nextPage(self, offset):
          """Retrieves the next set of results from the service."""
          self.logger.debug("Iterator crecord=%s" % str(self.crecord))
          params = {
              'q': self.q,
              'start': str(offset),
              'rows': str(self.pagesize),
              'fl': self.fields,
              'explainOther': '',
              'hl.fl': '',
          }
          if self.fq is not None:
              params['fq'] = self.fq
          self.res = self.client.search(params)
          self._numhits = int(self.res['response']['numFound'])