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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 roll50(msg):
 """Roll angle, BDS 5,0 message Args: msg (String):
 28 bytes hexadecimal message (BDS50) string Returns: float: angle in degrees, negative->left wing down, positive->right wing down """

    d = hex2bin(data(msg))

    if d[0] == '0':
        return None

    sign = int(d[1])    # 1 -> left wing down
    value = bin2int(d[2:11])

    if sign:
        value = value - 512

    angle = value * 45.0 / 256.0    # degree
    return round(angle, 1)