Validating the Signature

public static final String SIGNING_KEY_ALGO = "HMACSHA256";
public static boolean isSignatureValid(String payload, String receivedSignature, String signingKey) throws NoSuchAlgorithmException, InvalidKeyException, UnsupportedEncodingException {
     Mac mac = Mac.getInstance(SIGNING_KEY_ALGO);
     SecretKeySpec secretKeySpec =
             new SecretKeySpec(
                     signingKey.getBytes(StandardCharsets.UTF_8), SIGNING_KEY_ALGO);
     mac.init(secretKeySpec);

     String signature =
             org.apache.commons.codec.binary.Base64.encodeBase64String(mac.doFinal(payload.getBytes(StandardCharsets.UTF_8)));
     if(signature.equals(receivedSignature))
     {
         return true;
     }
     return false;
}

import hmac
import hashlib
import base64

def is_signature_valid(payload, received_signature, signing_key):
    mac = hmac.new(signing_key.encode('latin-1'), digestmod=hashlib.sha256)
    mac.update(payload.encode('latin-1'))
    signature = base64.b64encode(mac.digest()).decode('utf-8')

    return signature == received_signature