text: const config = {app: {port: 3000}}
  config.credentials = {};
  
  config.credentials.auth_id = 'PLIVO_AUTH_ID';
  config.credentials.auth_token = 'PLIVO_AUTH_TOKEN';
  config.app_number = 'PLIVO_NUMBER';
  config.phlo_id = null;
  
  module.exports = config;