s the index of the subplot being created.
            *index* starts at 1 in the upper left corner and increases to the
            right.

            If *nrows*, *ncols*, and *index* are all single digit numbers, then
            *args* can be passed as a single 3-digit number (e.g. 234 for
            (2, 3, 4)).
        horizontal : list of :mod:`~mpl_toolkits.axes_grid1.axes_size`, optional
            Sizes for horizontal division.
        vertical : list of :mod:`~mpl_toolkits.axes_grid1.axes_size`, optional
            Sizes for vertical division.
        aspect : bool, optional
            Whether overall rectangular area is reduced so that the relative
            part of the horizontal and vertical scales have the same scale.
        anchor : (float, float) or {'C', 'SW', 'S', 'SE', 'E', 'NE', 'N', 'NW', 'W'}, default: 'C'
            Placement of the reduced rectangle, when *aspect* is True.
        )