def service_group(self, service_name):
    """
    Args:
      service_name: the name of the service in the service registry
    Returns:
      the name of the group the service is in, or None of the service was not found
    """
    for group in EFConfig.SERVICE_GROUPS:
      if self.services(group).has_key(service_name):
        return group
    return None
Args:
      service_name: the name of the service in the service registry
    Returns:
      the name of the group the service is in, or None of the service was not found