'Adds a handler for the given watch.
:param event_handler:
An event handler instance that has appropriate event handling
methods which will be called by the observer in response to
file system events.
:type event_handler:
:class:`watchdog.events.FileSystemEventHandler` or a subclass
:param watch:
The watch to add a handler for.
:type watch:
An instance of :class:`ObservedWatch` or a subclass of
:class:`ObservedWatch`'

def add_handler_for_watch(self, event_handler, watch):

    with self._lock:
        self._add_handler_for_watch(event_handler, watch)
