code: function Logger() {
    this._level = LEVELS.NOTICE;
    this._out = process.stdout;
    this._err = process.stderr;
  
    /* istanbul ignore next: allow server to suppress logs */
    if(process.env.NODE_ENV === Constants.TEST && !process.env.TEST_DEBUG) {
      this.log = function noop(){};
    }
  }
docs: Create a logger.