'Call `list_users_in_group` with `password_expires_at` filter.
GET /groups/{group_id}/users?password_expires_at=
{operator}:{timestamp}&{operator}:{timestamp}'

def _list_users_in_group_by_password_expires_at(self, time, operator=None, expected_status=http_client.OK):

    url = (('/groups/' + self.group_id) + '/users?password_expires_at=')
    if operator:
        url += (operator + ':')
    url += str(time)
    return url
