docs: def set_based_on_grades(self, grades):
          """Sets the grade-based designation.
  
          arg:    grades (boolean): the grade-based designation
          raise:  InvalidArgument - ``grades`` is invalid
          raise:  NoAccess - ``grades`` cannot be modified
          *compliance: mandatory -- This method must be implemented.*
  
          """
          # Implemented from template for osid.resource.ResourceForm.set_group_template
          if self.get_based_on_grades_metadata().is_read_only():
              raise errors.NoAccess()
          if not self._is_valid_boolean(grades):
              raise errors.InvalidArgument()
          self._my_map['basedOnGrades'] = grades