code: private JSONObject setInternal( String key, Object value, JsonConfig jsonConfig ) {
        return _setInternal( key, processValue( key, value, jsonConfig ), jsonConfig );
     }
docs: Put a key/value pair in the JSONObject.
  
  @param key A key string.
  @param value An object which is the value. It should be of one of these
  types: Boolean, Double, Integer, JSONArray, JSONObject, Long,
  String, or the JSONNull object.
  @return this.
  @throws JSONException If the value is non-finite number or if the key is
  null.