code: func (u *utils) EncryptPEMBlock(data, password []byte) (*pem.Block, error) {
  	if IsPKCS8(data) {
  		return pkcs8.EncryptPEMBlock(data, password)
  	} else if u.fips {
  		return nil, ErrFIPSUnsupportedKeyFormat
  	}
  
  	cipherType := x509.PEMCipherAES256
  	return x509.EncryptPEMBlock(cryptorand.Reader,
  		"EC PRIVATE KEY",
  		data,
  		password,
  		cipherType)
  }
docs: // EncryptPEMBlock takes DER-format bytes and password to return an encrypted PKCS#1 or PKCS#8 PEM-block
  // It returns an error in FIPS mode when PKCS#1 PEM bytes are passed.