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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 post(self):
 """ Create a new directory at the specified path. """

        filepath = self.get_body_argument('filepath')

        try:
            self.fs.create_directory(filepath)
            encoded_filepath = tornado.escape.url_escape(filepath,plus=True)
            resource_uri = self.reverse_url('filesystem:directories-details', encoded_filepath)
            self.write({'uri':resource_uri})
        except OSError:
            raise tornado.web.HTTPError(404)