def createSignature(clientId, apiKey, privateKey, nonce):
 message = str(nonce) + str(clientId) + apiKey
 signature = hmac.new(privateKey, message, digestmod=hashlib.sha256).hexdigest()

function createSignature($id, $pk, $sk, $nonce){
     $message = $nonce . $id . $pk;
     $signature = hash_hmac('sha256', $message, $sk, false);
}