@classmethod
def get_certbot_paths(cls, domain):
    """Returns a tuple of paths for files (certificates_chain, private_key)
        from Certbot https://certbot.eff.org

        Those paths can be used to pass into Socket initializer.

        .. note:: If files not found empty strings are returned.

        :param str domain: Domain name to get filepaths for.

        :rtype: tuple[str, str]

        """
    from pathlib import Path
    certs_root = Path('/etc/letsencrypt/live/')
    certs_chain = certs_root / domain / 'fullchain.pem'
    certs_private = certs_root / domain / 'privkey.pem'
    if certs_chain.exists() and certs_private.exists():
        return str(certs_chain), str(certs_private)
    return '', ''
