code: func (k *Keyring) ImportSigningKey(pub *[ed25519.PublicKeySize]byte, sec *[ed25519.PrivateKeySize]byte) {
  	nk := NewSigningSecretKey(pub, sec)
  	k.sigKeys[nk.pub] = nk
  }
docs: // ImportSigningKey imports the raw signing key into the keyring.