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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 decrypted_message_from_bytes(bytestring, session_keys=None):
 """Create a Message from bytes. :param bytes bytestring: an email message as raw bytes :param session_keys: a list OpenPGP session keys """

    return decrypted_message_from_message(
        email.message_from_bytes(bytestring, policy=email.policy.SMTP),
        session_keys)