func (v *Voter) Execute(c []message.Command) ([]interface{}, error) {
	if c == nil || len(c) == 0 {
		fmt.Fprintln(os.Stderr, "From: No op")
	} else {
		for i := range c {
			fmt.Fprintln(os.Stderr, string(c[i]))
		}
	}
	return nil, nil
}
NOTE: This is not idempotent.
Same command might be executed for multiple times
but the exection is slow now, so it is unlikely to happen
package main
import (
	"flag"
	"fmt"
	"math/rand"
	"os"
	"strconv"
	"time"
	"github.com/go-distributed/epaxos/message"
	"github.com/go-distributed/epaxos/replica"
	"github.com/go-distributed/epaxos/transporter"
	"github.com/golang/glog"
)
var _ = fmt.Printf
const (
	chars           = "ABCDEFG"
	prepareInterval = 1  
)
type Voter struct{}