code: func WithMacvlan(parent string) func(*types.NetworkCreate) {
  	return func(n *types.NetworkCreate) {
  		n.Driver = "macvlan"
  		if parent != "" {
  			n.Options = map[string]string{
  				"parent": parent,
  			}
  		}
  	}
  }
docs: // WithMacvlan sets the network as macvlan with the specified parent