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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 _adjust(hsl, attribute, percent):
 """Internal adjust function"""

    hsl = list(hsl)
    if attribute > 0:
        hsl[attribute] = _clamp(hsl[attribute] + percent)
    else:
        hsl[attribute] += percent

    return hsl