code: func (ks *KeyStore) TimedUnlock(account *Account, passphrase string, timeout int64) error {
  	return ks.keystore.TimedUnlock(account.account, passphrase, time.Duration(timeout))
  }
docs: // TimedUnlock unlocks the given account with the passphrase. The account stays
  // unlocked for the duration of timeout (nanoseconds). A timeout of 0 unlocks the
  // account until the program exits. The account must match a unique key file.
  //
  // If the account address is already unlocked for a duration, TimedUnlock extends or
  // shortens the active unlock timeout. If the address was previously unlocked
  // indefinitely the timeout is not altered.