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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 set_color(index, color):
 """Convert a hex color to a text color sequence."""

    if OS == "Darwin" and index < 20:
        return "\033]P%1x%s\033\\" % (index, color.strip("#"))

    return "\033]4;%s;%s\033\\" % (index, color)