code: function random(len) {
      if (subtle) {
          return safeRandom(len);
      } else if (nodeCrypto) {
          return new Uint8Array(nodeCrypto.randomBytes(len));
      } else {
          throw new KdbxError(Consts.ErrorCodes.NotImplemented, 'Random not implemented');
      }
  }
docs: Generates random bytes of specified length
  @param {Number} len
  @returns {Uint8Array}