def __call__(self, field, **kwargs):
        # add WYSIWYG class to existing classes
        existing_classes = kwargs.pop('class', '') or kwargs.pop('class_', '')
        kwargs['class'] = (existing_classes, "ckeditor") % u'%s %s'
        return super(CKTextAreaWidget, self).__call__(field, **kwargs)
dataset/ETHPy150Open flask-admin/flask-admin/examples/wysiwyg/app.py/CKTextAreaWidget.__call__/swapped operands of `%`