def saturate(self, level):
h, s, l = self.__hsl<EOL>return Color((h, min(s + level, <NUM_LIT:1>), l), '<STR_LIT>', self.__a, self.__wref)<EOL>
Create a new instance based on this one but more saturated.

        Parameters:
          :level:
            The amount by which the color should be saturated to produce
            the new one [0...1].

        Returns:
          A grapefruit.Color instance.

        >>> Color.from_hsl(30, 0.5, 0.5).saturate(0.25)
        Color(0.875, 0.5, 0.125, 1.0)
        >>> Color.from_hsl(30, 0.5, 0.5).saturate(0.25).hsl
        (30.0, 0.75, 0.5)