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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def save_embed_js(target="", version=wembed.__html_manager_version__):
 """Download and save the ipywidgets embedding javascript to a local file. :type target: str :type version: str """

    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