         }
         let nonce = nonceAndAuthenticatedCipherText.subdata(with: NSRange(0..<NonceBytes)) as Nonce
         let authenticatedCipherText = nonceAndAuthenticatedCipherText.subdata(with: NSRange(NonceBytes..<nonceAndAuthenticatedCipherText.length))
-        return open(authenticatedCipherText, beforenm: beforenm, nonce: nonce)
+        return  open(authenticatedCipherText: authenticatedCipherText, beforenm: beforenm, nonce: nonce)
     }
 
     public func open(authenticatedCipherText: NSData, beforenm: Beforenm, nonce: Nonce) -> NSData? {

    }
    
    public func seal(message: NSData, recipientPublicKey: PublicKey, senderSecretKey: SecretKey) -> NSData? {
        guard let (authenticatedCipherText, nonce): (NSData, Nonce) = seal(message, recipientPublicKey: recipientPublicKey, senderSecretKey: senderSecretKey) else {
            return nil
        }
        let nonceAndAuthenticatedCipherText = NSMutableData(data: nonce as Data)

    }

    public func seal(message: NSData, beforenm: Beforenm) -> NSData? {
        guard let (authenticatedCipherText, nonce): (NSData, Nonce) = seal(message: message, beforenm: beforenm) else {
            return nil
        }
        let nonceAndAuthenticatedCipherText = NSMutableData(data: nonce as Data)
