def METHOD_NAME(url='http://qutebrowser.org/'):
    metadata = QNetworkCacheMetaData()
    metadata.setUrl(QUrl(url))
    # https://codereview.qt-project.org/c/qt/qtbase/+/465547
    metadata.setRawHeaders([(b"X-Hello", b"World")])
    assert metadata.isValid()
    assert metadata.rawHeaders()
    return metadata