code: def get_png_img_html(blob: Union[bytes, memoryview],
                       extra_html_class: str = None) -> str:
      
      return """<img {}src="{}" />""".format(
          'class="{}" '.format(extra_html_class) if extra_html_class else "",
          get_png_data_url(blob)
      )
docs: Converts a PNG blob to an HTML IMG tag with embedded data.