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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 createRect(self, x, y, width, height, rx=None, ry=None, strokewidth=1, stroke='black', fill='none'):
 """ Creates a Rectangle @type x: string or int @param x: starting x-coordinate @type y: string or int @param y: starting y-coordinate @type width: string or int @param width: width of the rectangle @type height: string or int @param height: height of the rectangle @type rx: string or int @param rx: For rounded rectangles, the x-axis radius of the ellipse used to round off the corners of the rectangle. @type ry: string or int @param ry: For rounded rectangles, the y-axis radius of the ellipse used to round off the corners of the rectangle. @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: a rect object """

        style_dict = {'fill':fill, 'stroke-width':strokewidth, 'stroke':stroke}
        myStyle = StyleBuilder(style_dict)
        r = Rect(x, y, width, height, rx, ry)
        r.set_style(myStyle.getStyle())
        return r