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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 _inject_specs(self, specs):
 """Injects targets into the graph for the given `Specs` object. Yields the resulting addresses. """

    if not specs:
      return

    logger.debug('Injecting specs to %s: %s', self, specs)
    with self._resolve_context():
      thts, = self._scheduler.product_request(TransitiveHydratedTargets,
                                              [specs])

    self._index(thts.closure)

    for hydrated_target in thts.roots:
      yield hydrated_target.address