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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _tls_auth_encrypt(self, s):
 """ Return the TLSCiphertext.encrypted_record for AEAD ciphers. """

        wcs = self.tls_session.wcs
        write_seq_num = struct.pack("!Q", wcs.seq_num)
        wcs.seq_num += 1
        return wcs.cipher.auth_encrypt(s, b"", write_seq_num)