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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 compute_reverse_dependencies( self, targets: Iterable[BuildTarget] ) -> Mapping[str, Iterable[BuildTarget]]: """ Compute the set of targets which depend on each target. """

        result = defaultdict(list)
        for target in targets:
            for dependency in target.dependencies:
                result[dependency].append(target)
        return result