+ @property
+ def tree_effort(self) -> float:
+ """Return sum of performed efforts of self and all descendants."""
+
+ def walk_tree(node: Todo) -> float:
+ local_effort = 0.0
+ for child in node.children:
+ local_effort += walk_tree(child)
+ return node.performed_effort + local_effort
+
+ return walk_tree(self)
+