去如何实现python binascii.unhexlify方法?

In my company there is a system written in python and I want to reimplement it using golang.

Question

Python binascii.unhexlify seems complex, and I don't know hot to implement it in go.

binascii.unhexlify method is simple enough. It's just converting from hex to binary. Every two hex digits is an 8-bit byte (256 possible values). here is my code

func unhexlify(str string) []byte {
    res := make([]byte, 0)
    for i := 0; i < len(str); i+=2 {
        x, _ := strconv.ParseInt(str[i:i+2], 16, 32)
        res = append(res, byte(x))
    }
    return res
}

I should use the library

func ExampleDecodeString() {
    const s = "48656c6c6f20476f7068657221"
    decoded, err := hex.DecodeString(s)
    if err != nil {
        log.Fatal(err)
    }

    fmt.Printf("%s
", decoded)

    // Output:
    // Hello Gopher!
}