code: def add_group_members(self, members):
          
          if not isinstance(members, list):
              members = [members]
  
          if not getattr(self, 'group_members', None):
              self.group_members = members
          else:
              self.group_members.extend(members)
docs: Add a new group member to the groups list
  
          :param members: member name
          :type members: str
          :return: None