code: def search_phenotype(
              self, phenotype_association_set_id=None, phenotype_id=None,
              description=None, type_=None, age_of_onset=None):
          
          request = protocol.SearchPhenotypesRequest()
          request.phenotype_association_set_id = phenotype_association_set_id
          if phenotype_id:
              request.id = phenotype_id
          if description:
              request.description = description
          if type_:
              request.type.mergeFrom(type_)
          if age_of_onset:
              request.age_of_onset = age_of_onset
          request.page_size = pb.int(self._page_size)
          return self._run_search_request(
              request, "phenotypes",
              protocol.SearchPhenotypesResponse)
docs: Returns an iterator over the Phenotypes from the server