code: def _get_filter_op_name_and_values(directive):
      
      args = get_uniquely_named_objects_by_name(directive.arguments)
      if 'op_name' not in args:
          raise AssertionError(u'op_name not found in filter directive arguments!'
                               u'Validation should have caught this: {}'.format(directive))
  
      # HACK(predrag): Workaround for graphql-core validation issue
      #                https://github.com/graphql-python/graphql-core/issues/97
      if not isinstance(args['value'].value, ListValue):
          raise GraphQLValidationError(u'Filter directive value was not a list: {}'.format(directive))
  
      op_name = args['op_name'].value.value
      operator_params = [x.value for x in args['value'].value.values]
  
      return (op_name, operator_params)
docs: Extract the (op_name, operator_params) tuple from a directive object.