Update TaskState documentation about dependents attribute
@@ -104,7 +104,10 @@ class TaskState:
* **dependencies**: ``set(TaskState instances)``
The data needed by this key to run
* **dependents**: ``set(TaskState instances)``
- The keys that use this dependency
+ The keys that use this dependency. Only keys which are not available
+ already are tracked in this structure and dependents made available are
+ actively removed. Only after all dependents have been removed, this task
+ is allowed to be forgotten
* **duration**: ``float``
Expected duration the a task
* **priority**: ``tuple``
