crypto: requested hash function #5 is unavailable

使用golang编码计算sha256加密，运行时报错panic: crypto: requested hash function #5 is unavailable

先贴一下源码：

package main

import (
	"crypto"
	"encoding/hex"
	"fmt"
)

func main() {
   
   
	s := "Transfer(address,address,uint256)"
	m := crypto.SHA256.New(</