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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 createPolyline(self, points, strokewidth=1, stroke='black'):
 """ Creates a Polyline @type points: string in the form "x1,y1 x2,y2 x3,y3" @param points: all points relevant to the polygon @type strokewidth: string or int @param strokewidth: width of the pen used to draw @type stroke: string (either css constants like "black" or numerical values like "#FFFFFF") @param stroke: color with which to draw the outer limits @return: a polyline object """

        style_dict = {'fill':'none', 'stroke-width':strokewidth, 'stroke':stroke}
        myStyle = StyleBuilder(style_dict)
        p = Polyline(points=points)
        p.set_style(myStyle.getStyle())
        return p