code: func (actor Actor) GetOrphanedRoutesBySpace(spaceGUID string) ([]Route, Warnings, error) {
  	var (
  		orphanedRoutes []Route
  		allWarnings    Warnings
  	)
  
  	routes, warnings, err := actor.GetSpaceRoutes(spaceGUID)
  	allWarnings = append(allWarnings, warnings...)
  	if err != nil {
  		return nil, allWarnings, err
  	}
  
  	for _, route := range routes {
  		apps, warnings, err := actor.GetRouteApplications(route.GUID)
  		allWarnings = append(allWarnings, warnings...)
  		if err != nil {
  			return nil, allWarnings, err
  		}
  
  		if len(apps) == 0 {
  			orphanedRoutes = append(orphanedRoutes, route)
  		}
  	}
  
  	if len(orphanedRoutes) == 0 {
  		return nil, allWarnings, actionerror.OrphanedRoutesNotFoundError{}
  	}
  
  	return orphanedRoutes, allWarnings, nil
  }
docs: // GetOrphanedRoutesBySpace returns a list of orphaned routes associated with
  // the provided Space GUID.