code: def get_field(self, field_name_or_ref_name, project=None):
          
          route_values = {}
          if project is not None:
              route_values['project'] = self._serialize.url('project', project, 'str')
          if field_name_or_ref_name is not None:
              route_values['fieldNameOrRefName'] = self._serialize.url('field_name_or_ref_name', field_name_or_ref_name, 'str')
          response = self._send(http_method='GET',
                                location_id='b51fd764-e5c2-4b9b-aaf7-3395cf4bdd94',
                                version='5.1-preview.2',
                                route_values=route_values)
          return self._deserialize('WorkItemField', response)
docs: GetField.
          [Preview API] Gets information on a specific field.
          :param str field_name_or_ref_name: Field simple name or reference name
          :param str project: Project ID or project name
          :rtype: :class:`<WorkItemField> <azure.devops.v5_1.work-item-tracking.models.WorkItemField>`