code: func (c *Computer) Unlock(pw string) {
  	print("UNLOCK <", pw, ">\n")
  	print(hex.Dump([]byte(pw)))
  	c.crypto.unlock(pw)
  }
docs: // Unlock records the password to use when decrypting
  // backups from this computer.  It must be called before calling Trees
  // in any folder obtained for this computer.