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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 trigger(self_, *param_names):
 """ Trigger watchers for the given set of parameter names. Watchers will be triggered whether or not the parameter values have actually changed. """

        events = self_.self_or_cls.param._events
        watchers = self_.self_or_cls.param._watchers
        self_.self_or_cls.param._events  = []
        self_.self_or_cls.param._watchers = []
        param_values = dict(self_.get_param_values())
        params = {name: param_values[name] for name in param_names}
        self_.self_or_cls.param._TRIGGER = True
        self_.set_param(**params)
        self_.self_or_cls.param._TRIGGER = False
        self_.self_or_cls.param._events = events
        self_.self_or_cls.param._watchers = watchers