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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_app_config(app_id):
 """ Get specific configuration for 'app_id'. """

    try:
        req = requests.get(
            ("https://clients3.google.com/"
             "cast/chromecast/device/app?a={}").format(app_id))

        return json.loads(req.text[4:]) if req.status_code == 200 else {}

    except ValueError:
        # If json fails to parse
        return {}