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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 createEllipse(self, cx, cy, rx, ry, strokewidth=1, stroke='black', fill='none'):
 """ Creates an ellipse @type cx: string or int @param cx: starting x-coordinate @type cy: string or int @param cy: starting y-coordinate @type rx: string or int @param rx: radius in x direction @type ry: string or int @param ry: radius in y direction @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 @type fill: string (either css constants like "black" or numerical values like "#FFFFFF") @param fill: color with which to fill the element (default: no filling) @return: an ellipse object """

        style_dict = {'fill':fill, 'stroke-width':strokewidth, 'stroke':stroke}
        myStyle = StyleBuilder(style_dict)
        e = Ellipse(cx, cy, rx, ry)
        e.set_style(myStyle.getStyle())
        return e