code: def x_pos(self, xval):
          "Return the x position (on the canvas) corresponding to XVAL."
          off = self.x_coord.get_canvas_pos(self.size[0], xval,
                                            self.x_range[0], self.x_range[1])
          return self.loc[0] + off x_pos(self, xval):
          "Return the x position (on the canvas) corresponding to XVAL."
          off = self.x_coord.get_canvas_pos(self.size[0], xval,
                                            self.x_range[0], self.x_range[1])
          return self.loc[0] + off
docs: Return the x position (on the canvas) corresponding to XVAL.