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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 unhold(self):
        ''' Turn off any active document hold and apply any collected events.

        Returns:
            None

        '''
        # no-op if we are already no holding
        if self._hold is None: return

        self._hold = None
        events = list(self._held_events)
        self._held_events = []

        for event in events:
            self._trigger_on_change(event)