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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_params_changed(self, trigger_parent=True):
 """ First tell all children to update, then update yourself. If trigger_parent is True, we will tell the parent, otherwise not. """

        [p._trigger_params_changed(trigger_parent=False) for p in self.parameters if not p.is_fixed]
        self.notify_observers(None, None if trigger_parent else -np.inf)