// is given, it sets default dial function.
//
// You can use returned dial function for `http.Transport.DialContext`.
//
// In this function, it uses functions from `rand` package. To make it really random,
// you MUST call `rand.Seed` and change the value from the default in your application
func DialContextWithLookupHost(lookupHost LookupHost, baseDialCtx DialContext) DialContext {
	if lookupHost == nil {