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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_executed_notebook(self):
 """Return the executed notebook."""

        r = requests.get('http://{0}/api/notebook/{1}'.format(
                         self.zeppelin_url, self.notebook_id))
        if r.status_code == 200:
            return r.json()['body']
        else:
            print('ERROR: Could not get executed notebook.', file=sys.stderr)
            sys.exit(1)