如何将字符串转换为固定字节数？

import sys

def convert_to_fixed_bytes(string, fixed_length, encoding='utf-8'):
    byte_array = string.encode(encoding)[:fixed_length]
    if len(byte_array) < fixed_length:
        byte_array += b'\x00' * (fixed_length - len(byte_array))
    return byte_array

string = "Hello, World!"
fixed_length = 10
fixed_bytes = convert_to_fixed_bytes(string, fixed_length)
print(fixed_bytes)

import java.nio.charset.StandardCharsets;
import java.util.Arrays;

public class StringToFixedBytes {
    public static byte[] convertToFixedBytes(String string, int fixedLength, String encoding) {
        byte[] byteArray = string.getBytes(encoding);
        if (byteArray.length < fixedLength) {
            byteArray = Arrays.copyOf(byteArray, fixedLength);
        } else if (byteArray.length > fixedLength) {
            byteArray = Arrays.copyOfRange(byteArray, 0, fixedLength);
        }
        return byteArray;
    }

    public static void main(String[] args) {
        String string = "Hello, World!";
        int fixedLength = 10;
        byte[] fixedBytes = convertToFixedBytes(string, fixedLength, StandardCharsets.UTF_8.name());
        System.out.println(Arrays.toString(fixedBytes));
    }
}