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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 GET(self, *args):
        '''
        Serve a single static file ignoring the remaining path

        This is useful in combination with a browser-based app using the HTML5
        history API.

        .. http::get:: /app

            :reqheader X-Auth-Token: |req_token|

            :status 200: |200|
            :status 401: |401|
        '''
        apiopts = cherrypy.config['apiopts']

        default_index = os.path.abspath(os.path.join(
            os.path.dirname(__file__), 'index.html'))

        return cherrypy.lib.static.serve_file(
                apiopts.get('app', default_index))