code: func IsRemoved(ctx context.Context, client client.NetworkAPIClient, networkID string) func(log poll.LogT) poll.Result {
  	return func(log poll.LogT) poll.Result {
  		_, err := client.NetworkInspect(ctx, networkID, types.NetworkInspectOptions{})
  		if err == nil {
  			return poll.Continue("waiting for network %s to be removed", networkID)
  		}
  		return poll.Success()
  	}
  }
docs: // IsRemoved verifies the network is removed.