def fill_stroke(self, fill = None, stroke = None, opacity = 1, line_width = None):
        """fill and stroke the drawn area in one go"""
        if line_width: self.set_line_style(line_width)

        if fill and stroke:
            self.fill_preserve(fill, opacity)
        elif fill:
            self.fill(fill, opacity)

        if stroke:
            self.stroke(stroke)
fill and stroke the drawn area in one go