code: func (a *AccountService) Deactivate(accountURL string) error {
  	if len(accountURL) == 0 {
  		return errors.New("account[deactivate]: empty URL")
  	}
  
  	req := acme.Account{Status: acme.StatusDeactivated}
  	_, err := a.core.post(accountURL, req, nil)
  	return err
  }
docs: // Deactivate Deactivates an account.