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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 collapse(self, remove=False):
 """ Move all ``sequence_ids`` in the subtree below this node to this node. If ``remove`` is True, nodes below this one are deleted from the taxonomy. """

        descendants = iter(self)
        # Skip this node
        assert next(descendants) is self
        for descendant in descendants:
            self.sequence_ids.update(descendant.sequence_ids)
            descendant.sequence_ids.clear()

        if remove:
            for node in self.children:
                self.remove_child(node)