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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 disable_user():
 """ Disables a user in the data store .. example:: $ curl http://localhost:5000/disable_user -X POST \ -H "Authorization: Bearer <your_token>" \ -d '{"username":"Walter"}' """

    req = flask.request.get_json(force=True)
    usr = User.query.filter_by(username=req.get('username', None)).one()
    usr.is_active = False
    db.session.commit()
    return flask.jsonify(message='disabled user {}'.format(usr.username))