code: func fetchCRL(url string) (*pkix.CertificateList, error) {
  	resp, err := http.Get(url)
  	if err != nil {
  		return nil, err
  	} else if resp.StatusCode >= 300 {
  		return nil, errors.New("failed to retrieve CRL")
  	}
  
  	body, err := crlRead(resp.Body)
  	if err != nil {
  		return nil, err
  	}
  	resp.Body.Close()
  
  	return x509.ParseCRL(body)
  }
docs: // fetchCRL fetches and parses a CRL.