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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 saturate_colors(colors, amount):
 """Saturate all colors."""

    if amount and float(amount) <= 1.0:
        for i, _ in enumerate(colors):
            if i not in [0, 7, 8, 15]:
                colors[i] = util.saturate_color(colors[i], float(amount))

    return colors