def get_dir_from_zipfile(zip_file, fallback=None):
    """Return the name of the root folder in a zip file.

    :param zip_file: a :class:`zipfile.ZipFile` instance.
    :param fallback: if `None`, the name of the zip file is used. This is
        returned if the zip file contains more than one top-level directory,
        or none at all.
    """
    fallback = fallback or zip_file.filename
    directories = [name for name in zip_file.namelist() if name.endswith("/")
                   and len(PurePath(name).parts) == 1]
    return fallback if len(directories) > 1 else directories[0]
def __init__(self):
        self.factory = yui.YUI.widgetFactory()
        self.dialog = self.factory.createPopupDialog()
        mainvbox = self.factory.createVBox(self.dialog)
        frame    = self.factory.createFrame(mainvbox,"Test frame")
        HBox     = self.factory.createHBox(frame)
        self.aboutbutton = self.factory.createPushButton(HBox,"&About")
        self.closebutton = self.factory.createPushButton(self.factory.createRight(HBox), "&Close")