docs: def is_obsoletes_pid(pid):
      """Return True if ``pid`` is referenced in the obsoletes field of any object.
  
      This will return True even if the PID is in the obsoletes field of an object that
      does not exist on the local MN, such as replica that is in an incomplete chain.
  
      """
      return d1_gmn.app.models.ScienceObject.objects.filter(obsoletes__did=pid).exists()