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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 _create_edge_by_target(self):
 """creates a edge_by_target dict with the same edge objects as the edge_by_source. Also adds an '@id' field to each edge."""

        ebt = {}
        for edge_dict in self._edge_by_source.values():
            for edge_id, edge in edge_dict.items():
                target_id = edge['@target']
                edge['@id'] = edge_id
                assert target_id not in ebt
                ebt[target_id] = edge
        # _check_rev_dict(self._tree, ebt)
        return ebt