code: func (s *MSPMessageCryptoService) ValidateIdentity(peerIdentity api.PeerIdentityType) error {
  	// As prescribed by the contract of method,
  	// below we check only that peerIdentity is not
  	// invalid, revoked or expired.
  
  	_, _, err := s.getValidatedIdentity(peerIdentity)
  	return err
  }
docs: // ValidateIdentity validates the identity of a remote peer.
  // If the identity is invalid, revoked, expired it returns an error.
  // Else, returns nil