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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 cadhumidex(temp, humidity):
    "Calculate Humidity Index as per Canadian Weather Standards"
    if temp is None or humidity is None:
        return None
    # Formulas are adapted to not use e^(...) with no appreciable
    # change in accuracy (0.0227%)
    saturation_pressure = (6.112 * (10.0**(7.5 * temp / (237.7 + temp))) *
                           float(humidity) / 100.0)
    return temp + (0.555 * (saturation_pressure - 10.0))