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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 compose_telegram(body):
 """ Compose a SCS message body: list containing the body of the message. returns: full telegram expressed (bytes instance) """


    msg = [b"A8"] + body + [checksum_bytes(body)] + [b"A3"]
    return str.encode("".join([x.decode() for x in msg]))