@classmethod
def UserWaterAndOzone(cls, water, ozone):
    """Set 6S to use an atmosphere defined by an amount of water vapour and ozone.

        Arguments:

        * ``water`` -- The total amount of water in a vertical path through the atmosphere (in g/cm^2)
        * ``ozone`` -- The total amount of ozone in a vertical path through the atmosphere (in cm-atm)

        Example usage::

          s.atmos_profile = AtmosProfile.UserWaterAndOzone(3.6, 0.9)

        """
    return '8 (Water Vapour and Ozone)\n%f %f' % (water, ozone)
