How to use the pytmx.pytmx.TiledImageLayer function in PyTMX

""" Parse a map from ElementTree xml node

        :param node: ElementTree xml node
        :return: self
        """
        self._set_properties(node)
        self.background_color = node.get('backgroundcolor',
                                         self.background_color)

        # ***         do not change this load order!         *** #
        # ***    gid mapping errors will occur if changed    *** #
        for subnode in node.findall('layer'):
            self.add_layer(TiledTileLayer(self, subnode))

        for subnode in node.findall('imagelayer'):
            self.add_layer(TiledImageLayer(self, subnode))

        for subnode in node.findall('objectgroup'):
            self.add_layer(TiledObjectGroup(self, subnode))

        for subnode in node.findall('tileset'):
            self.add_tileset(TiledTileset(self, subnode))

        # "tile objects", objects with a GID, have need to have their attributes
        # set after the tileset is loaded, so this step must be performed last
        # also, this step is performed for objects to load their tiles.

        # tiled stores the origin of GID objects by the lower right corner
        # this is different for all other types, so i just adjust it here
        # so all types loaded with pytmx are uniform.

        # iterate through tile objects and handle the image

# gids is None if the tile is never used
                # but give another chance to load the gid anyway
                if gids is None:
                    if self.load_all_tiles or real_gid in self.optional_gids:
                        # TODO: handle flags? - might never be an issue, though
                        gids = [self.register_gid(real_gid, flags=0)]

                if gids:
                    # flags might rotate/flip the image, so let the loader
                    # handle that here
                    for gid, flags in gids:
                        self.images[gid] = loader(rect, flags)

        # load image layer images
        for layer in (i for i in self.layers if isinstance(i, TiledImageLayer)):
            source = getattr(layer, 'source', None)
            if source:
                colorkey = getattr(layer, 'trans', None)
                real_gid = len(self.images)
                gid = self.register_gid(real_gid)
                layer.gid = gid
                path = os.path.join(os.path.dirname(self.filename), source)
                loader = self.image_loader(path, colorkey)
                image = loader()
                self.images.append(image)

        # load images in tiles.
        # instead of making a new gid, replace the reference to the tile that
        # was loaded from the tileset
        for real_gid, props in self.tile_properties.items():
            source = props.get('source', None)