code: function totpOptions(options = {}) {
    let opt = Object.assign(hotpOptions(), defaultOptions, options);
    opt.epoch = typeof opt.epoch === 'number' ? opt.epoch * 1000 : Date.now();
  
    return opt;
  }
docs: Generates options for TOTP
  
  @module otplib-core/totpOptions
  @param {number} options.digits - the output token length
  @param {string} options.epoch - starting time since the UNIX epoch (seconds)
  @param {number} options.step - time step (seconds)
  @param {number|array} options.window - acceptable window where codes a valid.
  @return {object}