code: func isDeletionDup(a, b *Delta) *Delta {
  	if b.Type != Deleted || a.Type != Deleted {
  		return nil
  	}
  	// Do more sophisticated checks, or is this sufficient?
  	if _, ok := b.Object.(DeletedFinalStateUnknown); ok {
  		return a
  	}
  	return b
  }
docs: // keep the one with the most information if both are deletions.