<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def parse(data):
 """ Parses a raw datagram and return the right type of message """


    # convert to string
    data = data.decode("ascii")

    if len(data) == 2 and data == "A5":
        return AckMessage()

    # split into bytes
    raw = [data[i:i+2] for i in range(len(data)) if i % 2 == 0]

    if len(raw) != 7:
        return UnknownMessage(raw)

    if raw[1] == "B8":
        return StateMessage(raw)
    elif raw[3] == "12":
        return CommandMessage(raw)
    elif raw[3] == "14":
        return ScenarioTriggeredMessage(raw)
    elif raw[3] == "15":
        return RequestStatusMessage(raw)
    else:
        return UnknownMessage(raw)