def __init__(self, signing_key, op_return, date_time_utc, revoked_addresses):
self.signing_key = signing_key<EOL>self.op_return = op_return<EOL>self.date_time_utc = parse_or_none(date_time_utc)<EOL>self.revoked_addresses = revoked_addresses<EOL>
:param signing_key: key used to sign the transaction
:param op_return: value in op_return field
:param date_time_utc: datetime in UTC
:param revoked_addresses: revoked addresses (pre-V2)