How to use the cairosvg.surface.cairo.SurfacePattern function in CairoSVG

pattern_height = (
            size(surface, pattern_node.pop('height', '1'), 1) * height)
        if 'viewBox' not in pattern_node:
            pattern_node['width'] = pattern_width
            pattern_node['height'] = pattern_height
            if pattern_node.get('patternContentUnits') == 'objectBoundingBox':
                pattern_node['transform'] = 'scale({}, {})'.format(
                    width, height)

    # Fail if pattern has an invalid size
    if pattern_width == 0.0 or pattern_height == 0.0:
        return False

    from .surface import SVGSurface  # circular import
    pattern_surface = SVGSurface(pattern_node, None, surface.dpi, surface)
    pattern_pattern = cairo.SurfacePattern(pattern_surface.cairo)
    pattern_pattern.set_extend(cairo.EXTEND_REPEAT)
    pattern_pattern.set_matrix(cairo.Matrix(
        pattern_surface.width / pattern_width, 0, 0,
        pattern_surface.height / pattern_height, -x, -y))
    surface.context.set_source(pattern_pattern)
    return True

surface.context.translate(translate_x, translate_y)
        surface.draw(tree)
        surface.context.restore()
        return
    else:
        png_file = BytesIO()
        image = Image.open(BytesIO(image_bytes))

        if surface.map_image:
            image = surface.map_image(image)

        image.save(png_file, 'PNG')
        png_file.seek(0)

    image_surface = cairo.ImageSurface.create_from_png(png_file)
    image_surface.pattern = cairo.SurfacePattern(image_surface)
    image_surface.pattern.set_filter(IMAGE_RENDERING.get(
        node.get('image-rendering'), cairo.FILTER_GOOD))

    node.image_width = image_surface.get_width()
    node.image_height = image_surface.get_height()
    scale_x, scale_y, translate_x, translate_y = preserve_ratio(
        surface, node)

    # Clip image region (if necessary)
    if not (translate_x == 0 and
            translate_y == 0 and
            width == scale_x * node.image_width and
            height == scale_y * node.image_height):
        surface.context.rectangle(x, y, width, height)
        surface.context.clip()

surface.context.translate(*surface.context.get_current_point())
        surface.context.scale(scale_x, scale_y)
        surface.context.translate(translate_x, translate_y)
        surface.draw(tree)
        surface.context.restore()
        return
    else:
        png_file = BytesIO()
        Image.open(BytesIO(image_bytes)).save(png_file, 'PNG')
        png_file.seek(0)

    image_surface = cairo.ImageSurface.create_from_png(png_file)

    ### DSB
    ## Added:
    image_surface.pattern = cairo.SurfacePattern(image_surface)
    image_surface.pattern.set_filter(cairo.FILTER_NEAREST)
    ### DSB

    node.image_width = image_surface.get_width()
    node.image_height = image_surface.get_height()
    scale_x, scale_y, translate_x, translate_y = preserve_ratio(
        surface, node)

    # Clip image region (if necessary)
    if not (translate_x == 0 and
            translate_y == 0 and
            width == scale_x * node.image_width and
            height == scale_y * node.image_height):
        surface.context.rectangle(x, y, width, height)
        surface.context.clip()