code: def count(self):
          
          request_params = dict(self.request_params)
          request_url = str(self.request_url)
          request_params['rows'] = 0
  
          result = self.do_http_request(
              'get',
              request_url,
              data=request_params,
              custom_header=str(self.etiquette)
          ).json()
  
          return int(result['message']['total-results'])
docs: This method retrieve the total of records resulting from a given query.
  
          This attribute can be used compounded with query, filter,
          sort, order and facet methods.
  
          Examples:
              >>> from crossref.restful import Works
              >>> Works().query('zika').count()
              3597
              >>> Works().query('zika').filter(prefix='10.1590').count()
              61
              >>> Works().query('zika').filter(prefix='10.1590').sort('published').order('desc').filter(has_abstract='true').count()
              14
              >>> Works().query('zika').filter(prefix='10.1590').sort('published').order('desc').filter(has_abstract='true').query(author='Marli').count()
              1