code: function prepareParams(msg, config) {
      var params = {},
        inputlang = config.inputlang ? config.inputlang : 'en',
        outputlang = config.outputlang ? config.outputlang : 'en';
  
      if (msg.piparams) {
        if (msg.piparams.inputlanguage &&
              -1 < VALID_INPUT_LANGUAGES.indexOf(msg.piparams.inputlanguage)) {
          inputlang = msg.piparams.inputlanguage;
        }
        if (msg.piparams.responselanguage &&
              -1 < VALID_RESPONSE_LANGUAGES.indexOf(msg.piparams.responselanguage)) {
          outputlang = msg.piparams.responselanguage;
        }
      }
  
      params = {
        content: msg.payload,
        consumption_preferences: config.consumption ? config.consumption : false,
        raw_scores: config.rawscores ? config.rawscores : false,
        headers: {
          'content-language': inputlang,
          'accept-language': outputlang,
          'accept': 'application/json'
        }
      };
  
      if ('string' === typeof msg.payload) {
        params.content_type = 'text/plain';
      } else {
        params.content_type = 'application/json';
      }
  
      return Promise.resolve(params);
    }
docs: This function prepares the params object for the call to Personality Insights