code: func (gce *Cloud) CreateURLMap(backend *compute.BackendService, name string) (*compute.UrlMap, error) {
  	urlMap := &compute.UrlMap{
  		Name:           name,
  		DefaultService: backend.SelfLink,
  	}
  	op, err := gce.service.UrlMaps.Insert(gce.projectID, urlMap).Do()
  	if err != nil {
  		return nil, err
  	}
  	if err = gce.waitForGlobalOp(op); err != nil {
  		return nil, err
  	}
  	return gce.GetURLMap(name)
  }
docs: // CreateURLMap creates an url map, using the given backend service as the default service.