New Go chaincode header import

import (
    "encoding/base64"
    "encoding/json"
    "fmt"
    "github.com/golang/protobuf/proto"
    "github.com/hyperledger/fabric-chaincode-go/shim"
    "github.com/hyperledger/fabric-protos-go/common"
    "github.com/hyperledger/fabric-protos-go/msp"
    pb "github.com/hyperledger/fabric-protos-go/peer"
    "math/rand"
    "time"
)