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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 decrypt(self, ciphertext, encoder=encoding.RawEncoder):
 """ Decrypts the ciphertext using the ephemeral public key enclosed in the ciphertext and the SealedBox private key, returning the plaintext message. :param ciphertext: [:class:`bytes`] The encrypted message to decrypt :param encoder: The encoder used to decode the ciphertext. :return bytes: The original plaintext """

        # Decode our ciphertext
        ciphertext = encoder.decode(ciphertext)

        plaintext = nacl.bindings.crypto_box_seal_open(
            ciphertext,
            self._public_key,
            self._private_key,
        )

        return plaintext