def METHOD_NAME(self, input_cubes: CubeList) -> Cube:
    """Check input cubes, then calculate and interpolate a snow fraction cube.
    Args:
        input_cubes:
            Contains cubes of rain and snow, both must be either rates or accumulations.
    Returns:
        Cube of snow-fraction. The data within this
        cube will contain values between 0 and 1. Points where no precipitation
        is present will be filled using a nearest-neighbour interpolation.
            The cube meta-data will contain:
            * Input_cube name "snow_fraction"
            * Cube units set to (1).
    Raises:
        ValueError: if input cubes fail any comparison tests.
    """
    self._get_input_cubes(input_cubes)
    return self._calculate_snow_fraction()