code: def register_list_auth_roles_command(self, list_auth_roles_func):
          
          description = "List authorization roles for use with add_user command."
          list_auth_roles_parser = self.subparsers.add_parser('list-auth-roles', description=description)
          list_auth_roles_parser.set_defaults(func=list_auth_roles_func)
docs: Add 'list_auth_roles' command to list project authorization roles that can be used with add_user.
          :param list_auth_roles_func: function: run when user choses this option.