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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 managed_dependencies(self):
 """The managed_jar_dependencies target this jar_library specifies, or None. :API: public """

    if self.payload.managed_dependencies:
      address = Address.parse(self.payload.managed_dependencies,
                              relative_to=self.address.spec_path)
      self._build_graph.inject_address_closure(address)
      return self._build_graph.get_target(address)
    return None