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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 template(cls, address=None, target=None, commandtuple=None, userdata=None, cmd2=-1, flags=None):
 """Create message template for callbacks."""

        msgraw = bytearray([0x02, cls._code])
        msgraw.extend(bytes(cls._receivedSize))
        msg = ExtendedReceive.from_raw_message(msgraw)

        if commandtuple:
            cmd1 = commandtuple.get('cmd1')
            cmd2out = commandtuple.get('cmd2')
        else:
            cmd1 = None
            cmd2out = None

        if cmd2 is not -1:
            cmd2out = cmd2

        msg._address = Address(address)
        msg._target = Address(target)
        msg._messageFlags = MessageFlags(flags)
        msg._cmd1 = cmd1
        msg._cmd2 = cmd2out
        msg._userdata = Userdata.create_pattern(userdata)
        return msg