Simple hello world in Go for Medium post

hello-world.go

package main

import (
 "fmt"
 "log"
 "net/http"
)

func main() {
http.HandleFunc("/", func(res http.ResponseWriter, req *http.Request) {
  fmt.Fprint(res, "Hello World")
 })
  
log.Println("Go Hello World listening on port 8123")
 http.ListenAndServe(":8123", nil)
}