def with_lightness(self, lightness):
h, s, l = self.__hsl<EOL>return Color((h, s, lightness), '<STR_LIT>', self.__a, self.__wref)<EOL>
Create a new instance based on this one with a new lightness value.

        Parameters:
          :lightness:
            The lightness of the new color [0...1].

        Returns:
          A grapefruit.Color instance.

        >>> Color.from_hsl(30, 1, 0.5).with_lightness(0.25)
        Color(0.5, 0.25, 0.0, 1.0)
        >>> Color.from_hsl(30, 1, 0.5).with_lightness(0.25).hsl
        (30.0, 1.0, 0.25)