human
Complete this python program:
def group_membership():
assistant
#Here is the Python program you requested.

    """RESTful CRUD controller for options.s3json lookups
    """
    if (auth.permission.format != 's3json'):
        return ''
    def prep(r):
        if (r.method != 'options'):
            return False
        return True
    s3.prep = prep
    return s3_rest_controller()