Returns tuple key rect of above left cell

def get_above_left_key_rect(self):
        """Returns tuple key rect of above left cell"""

        key_above_left = self.row - 1, self.col - 1, self.tab

        border_width_right = \
            float(self.cell_attributes[key_above_left]["borderwidth_right"]) \
            / 2.0
        border_width_bottom = \
            float(self.cell_attributes[key_above_left]["borderwidth_bottom"]) \
            / 2.0

        rect_above_left = (self.x-border_width_right,
                           self.y-border_width_bottom,
                           border_width_right, border_width_bottom)
        return key_above_left, rect_above_left