code: def save_embed_js(target="", version=wembed.__html_manager_version__):
      
      url = u'https://unpkg.com/@jupyter-widgets/html-manager@{0:s}/dist/embed-amd.js'.format(version)
      if version.startswith('^'):
          version = version[1:]
      filename = "embed-amd_v{0:s}.js".format(version)
      filepath = os.path.join(target, filename)
  
      download_to_file(url, filepath)
      return filename
docs: Download and save the ipywidgets embedding javascript to a local file.
  
      :type target: str
      :type version: str