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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 discard(self, interval):
 """ Removes an interval from the tree, if present. If not, does nothing. Completes in O(log n) time. """

        if interval not in self:
            return
        self.all_intervals.discard(interval)
        self.top_node = self.top_node.discard(interval)
        self._remove_boundaries(interval)