def calculate_hounsfield_unit(mu, mu_water, mu_air):
    """
    Given linear attenuation coefficients the function calculates the corresponding Hounsfield units.
    :param mu: Attenuation coefficient to determine corresponding Hounsfield unit.
    :param mu_water: Constant linear attenuation coefficient for water
    :param mu_air: Constant linear attenuation coefficient for air
    :return: Hounsfield unit corresponding to mu
    """

    HU = 1000 * ((mu - mu_water) / (mu_water - mu_air))

    return HU