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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def watch(self, path, action, *args, **kwargs):
 """ Called by the Server instance when a new watch task is requested. """

        if action is None:
            action = _set_changed
        event_handler = _WatchdogHandler(self, action)
        self._observer.schedule(event_handler, path=path, recursive=True)