code: def get_containers():
          
          LOGGER.debug("ContainerService.get_containers")
          params = SessionService.complete_transactional_req(None)
          if params is None:
              if MappingService.driver_type != DriverFactory.DRIVER_REST:
                  params = {'OPERATION': 'getContainers'}
                  args = {'properties': params}
              else:
                  args = {'http_operation': 'GET', 'operation_path': ''}
          else:
              if MappingService.driver_type != DriverFactory.DRIVER_REST:
                  params["OPERATION"] = "getContainers"
                  args = {'properties': params}
              else:
                  args = {'http_operation': 'GET', 'operation_path': '', 'parameters': params}
  
          response = ContainerService.requester.call(args)
  
          if MappingService.driver_type != DriverFactory.DRIVER_REST:
              response = response.get()
  
          ret = None
          if response.rc == 0:
              ret = []
              for container in response.response_content['containers']:
                  ret.append(Container.json_2_container(container))
          elif response.rc != 404:
              err_msg = 'ContainerService.get_containers - Problem while getting containers. ' \
                        'Reason: ' + str(response.response_content) + ' - ' + str(response.error_message) + \
                        " (" + str(response.rc) + ")"
              LOGGER.warning(err_msg)
              if response.rc == 500 and ArianeMappingOverloadError.ERROR_MSG in response.error_message:
                  raise ArianeMappingOverloadError("ContainerService.get_containers",
                                                   ArianeMappingOverloadError.ERROR_MSG)
              # traceback.print_stack()
          return ret
docs: get all known containers from Ariane Server
          :return: