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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 iscomplete(rawmessage):
 """Test if the raw message is a complete message."""

    if len(rawmessage) < 2:
        return False

    if rawmessage[0] != 0x02:
        raise ValueError('message does not start with 0x02')

    messageBuffer = bytearray()
    filler = bytearray(30)
    messageBuffer.extend(rawmessage)
    messageBuffer.extend(filler)

    msg = _get_msg_class(rawmessage[1])

    if hasattr(msg, 'receivedSize') and msg.receivedSize:
        expectedSize = msg.receivedSize
    else:
        _LOGGER.error('Unable to find a receivedSize for code 0x%x',
                      rawmessage[1])
        return ValueError

    is_expected_size = False
    if len(rawmessage) >= expectedSize:
        is_expected_size = True

    return is_expected_size