tx.go
func NewRequestTx(name string, url string) *tx {
	t := NewTx(name)
	t.url = url
	return t
}
func NewRequestTx(name string, url string) *tx {
	t := NewTx(name)
	t.url = url
	return t
}
func NewRequestTx ( name string , url string ) * tx { t := NewTx ( name ) t . url = url return t }
// NewRequestTx returns a new transaction with a request url.
NewRequestTx returns a new transaction with a request url .