def render_not_found_icon(size):
    """Return surface with icon representing an image not found.

    Icon is formed by an ellipse with a diagonal slash.

    Parameters
    ==========
    size (2-tuple of integers)
        Integers represent width and height of surface, respecively.
    """
    ### render an ellipse outline surface

    ## define ellipse data

    # outline thickness

    smaller_dimension = min(size)

    outline_thickness = (
        smaller_dimension // 10 if smaller_dimension > 10 else 1
    )

    # cx, cy, rx, ry

    cx, cy = (dimension/2 for dimension in size)

    rx = cx - (outline_thickness/2)
    ry = cy - (outline_thickness/2)

    ## render

    ellipse_outline_surf = (

        render_surface_from_svg_text(

            get_ellipse_svg_text(
                cx,
                cy,
                rx,
                ry,
                outline_color=IMAGE_NOT_FOUND_FG,
                outline_width=outline_thickness,
            )

        )

    )

    ### render a diagonal line surface

    ## find points of segment cutting ellipse

    rect = Rect(0, 0, *size)

    if outline_thickness > 1:

        deflation = -(outline_thickness - 1)
        rect.inflate_ip(deflation, deflation)

    (x1, y1), (x2, y2) = get_segment_points_cutting_ellipse(rect)

    ## render

    diagonal_line_surf = (

        render_surface_from_svg_text(

            get_line_svg_text(
                x1,
                y1,
                x2,
                y2,
                outline_color=IMAGE_NOT_FOUND_FG,
                outline_width=outline_thickness,
            )

        )

    )

    ### create base surface and blit other surfaces over it

    ellipse_surf = render_rect(*size, IMAGE_NOT_FOUND_BG)

    ellipse_surf.blit(ellipse_outline_surf, (0, 0))

    blit_aligned(
        surface_to_blit=diagonal_line_surf,
        target_surface=ellipse_surf,
        retrieve_pos_from='center',
        assign_pos_to='center',
    )

    ### finallly return the surface we created
    return ellipse_surf
Return surface with icon representing an image not found.

    Icon is formed by an ellipse with a diagonal slash.

    Parameters
    ==========
    size (2-tuple of integers)
        Integers represent width and height of surface, respecively.
    
nodezator/surfsman/render.py