How to use the zopfli.ZopfliPNG function in zopfli

:rtype: Asset
        """
        mime_type = MimeType(mime_type)

        pil_format = PillowProcessor.__mime_type_to_pillow_type[mime_type]
        pil_options = dict(PillowProcessor.__format_defaults.get(mime_type, {}))
        format_config = dict(self.config.get(mime_type.type, {}))
        format_config.update(self.config.get(str(mime_type), {}))

        image_buffer = io.BytesIO()

        if mime_type == MimeType('image/png') and image.mode != 'P':
            use_zopfli = format_config.get('zopfli', False)
            if use_zopfli:
                import zopfli
                zopfli_png = zopfli.ZopfliPNG()
                # Convert 16-bit per channel images to 8-bit per channel
                zopfli_png.lossy_8bit = False
                # Allow altering hidden colors of fully transparent pixels
                zopfli_png.lossy_transparent = True
                # Use all available optimization strategies
                zopfli_png.filter_strategies = format_config.get('zopfli_strategies', '0me')

                pil_options.pop('optimize', False)
                essence = io.BytesIO()
                image.save(essence, 'PNG', optimize=False, **pil_options)
                essence.seek(0)
                optimized_data = zopfli_png.optimize(essence.read())
                image_buffer.write(optimized_data)
            else:
                image.save(image_buffer, pil_format, **pil_options)
        elif mime_type == MimeType('image/jpeg'):

output_format = "jpeg"

    # convert / optimize
    output_image_bytes = None
    if output_format == "jpeg":
        output_image_bytes = pyguetzli.process_pil_image(
                image, int(options["jpeg_quality"] * 100))
    else:
        pass
        image_io = io.BytesIO()
        image.save(image_io, format="PNG", optimize=False)
        image_io.seek(0)
        image_bytes = image_io.read()

        # Optimize using zopflipng
        zopflipng = zopfli.ZopfliPNG()
        zopflipng.lossy_8bit = True
        zopflipng.lossy_transparent = True
        zopflipng.filter_strategies = "01234mepb"
        zopflipng.iterations = 20
        zopflipng.iterations_large = 7
        output_image_bytes = zopflipng.optimize(image_bytes)

    # write to output_file
    output_file.seek(0)
    output_file.truncate()
    output_file.write(output_image_bytes)