def ssl_context_for_root(ca_cert_file: str) -> Optional[ssl.SSLContext]:
    ssl_context = ssl.create_default_context(purpose=ssl.Purpose.SERVER_AUTH, cafile=ca_cert_file)
    return ssl_context
def ssl_context_for_root(ca_cert_file: str) -> Optional[ssl.SSLContext]:
    ssl_context = ssl.create_default_context(purpose=ssl.Purpose.SERVER_AUTH, cafile=ca_cert_file)
    return ssl_context