def error(self, g):
        message = "Invalid Expression"
        g.font = awt.Font('Serif', awt.Font.BOLD, 20)
        width = g.fontMetrics.stringWidth(message)

        x = (self.size.width-width)/2
        y = (self.size.height+g.fontMetrics.height)/2
        g.drawString("Invalid Expression", x, y)
dataset/ETHPy150Open azoft-dev-team/imagrium/env/Lib/test/Graph.py/Graph.error/original