def create_default_groups(self):
        for group in self.groups:
            group = group.replace(" ", "_").lower()
            self[group] = NamedRequirements(group)
def image_thumbnail(filename):
    filepath = os.path.join(app.config.get('UPLOAD_FOLDER'), filename)
    im = Image.open(filepath)
    w, h = im.size

    if w > h:
        im.thumbnail((106, 106*h/w))
    else:
        im.thumbnail((106*w/h, 106))

    im.save(os.path.join(app.config.get('UPLOAD_FOLDER'), 
        os.path.splitext(filename)[0] + '_thumbnail' + os.path.splitext(filename)[1]))