code: func (lca *CA) CACertificate() ([]byte, error) {
  	if lca.s == nil {
  		return nil, errNotSetup
  	}
  
  	cert, err := lca.s.Certificate(lca.Label, lca.Profile)
  	if err != nil {
  		return nil, err
  	}
  
  	p := &pem.Block{
  		Type:  "CERTIFICATE",
  		Bytes: cert.Raw,
  	}
  	return pem.EncodeToMemory(p), nil
  }
docs: // CACertificate returns the certificate authority's certificate.