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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_contourf_properties(stroke_width, fcolor, fill_opacity, contour_levels, contourf_idx, unit):
 """Set property values for Polygon."""

    return {
        "stroke": fcolor,
        "stroke-width": stroke_width,
        "stroke-opacity": 1,
        "fill": fcolor,
        "fill-opacity": fill_opacity,
        "title": "%.2f" % contour_levels[contourf_idx] + ' ' + unit
    }