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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def desaturate(self, level):
 """Create a new instance based on this one but less saturated. Parameters: :level: The amount by which the color should be desaturated to produce Returns: A grapefruit.Color instance. Color(0.625, 0.5, 0.375, 1.0) (30.0, 0.25, 0.5) """

    h, s, l = self.__hsl
    return Color((h, max(s - level, 0), l), 'hsl', self.__a, self.__wref)