leaders_extend_schema.py

   # Add this to the action
    
   @extend_schema(
        methods=("GET",),
        parameters=[OpenApiParameter("username", exclude=True)],
        description="Returns the list of users that have at least one user in charge.",
        responses=UserListSerializer(many=True),
    )
    @extend_schema(
        methods=("POST",),
        description="Receives the id of a user and a leader and sets the leader as leader of the user.",
        request=SetLeaderSerializer,
        responses=SetLeaderSerializer,
    )
    @action(detail=False, methods=("GET", "POST",))
    def leaders(self, request):
        ...