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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 knx2_to_float(knxdata):
 """Convert a KNX 2 byte float object to a float"""

    if len(knxdata) != 2:
        raise KNXException("Can only convert a 2 Byte object to float")

    data = knxdata[0] * 256 + knxdata[1]
    sign = data >> 15
    exponent = (data >> 11) & 0x0f
    mantisse = float(data & 0x7ff)
    if sign == 1:
        mantisse = -2048 + mantisse

    return mantisse * pow(2, exponent) / 100