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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 format_hsl(hsl_color):
 # type: (_HSL_COLOR) -> str """ Format hsl color as css color string. """

    hue, saturation, lightness = hsl_color
    return 'hsl({}, {:.2%}, {:.2%})'.format(hue, saturation, lightness)