python3 base64.b64decode Base64解碼報錯: Incorrect padding

import base64

def base64_decode(encode):
    """
    解決base64編碼結尾缺少=報錯的問題
    """
    missing_padding = 4 - len(encode) % 4
    if missing_padding:
        encode += '=' * missing_padding
    decode = base64.b64decode(encode)
    return decode

print(base64_decode("aGVsbG8="))
print(base64_decode("aGVsbG8"))

print(base64.b64decode("aGVsbG8"))