diff --git a/crypto/crypto.go b/crypto/crypto.go
index d0cf73cc9d..8422127ab0 100644
--- a/crypto/crypto.go
+++ b/crypto/crypto.go
@@ -23,12 +23,13 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
+	"io/ioutil"
+	"math/big"
+
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/math"
 	"github.com/ethereum/go-ethereum/rlp"
 	"golang.org/x/crypto/sha3"
-	"io/ioutil"
-	"math/big"
 )
 
 //SignatureLength indicates the byte length required to carry a signature with recovery id.