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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 rh45(msg):
 """Radio height. Args: msg (String):
 28 bytes hexadecimal message string Returns: int: radio height in ft """

    d = hex2bin(data(msg))
    if d[38] == '0':
        return None
    rh = bin2int(d[39:51]) * 16
    return rh