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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 remove(self, parent):
 """Remove an aggregation rule. Parameters parent : :class:`katcp.Sensor` object The aggregate sensor to remove. """

        if parent not in self._aggregates:
            raise ValueError("Sensor %r does not have an aggregate rule "
                             "associated" % parent)
        children = self.children(parent)
        try:
            self.remove_links(parent, children)
        except Exception:
            pass
        del self._aggregates[parent]