Watches
Collection of listeners.
Keys.
Values.
Listeners state.
Notifity all listeners that a key has changed. If the argument is None, this means the key has been removed.
None
Create in-memory notifications.
Clear all watches.
Create a stream of event notifications. Need to provide the initial value (or None if the key does not have associated contents yet).
Register a fsevents/inotify thread to look for changes in the given directory.