new_contents: #!/usr/bin/env python
  # Licensed to the StackStorm, Inc ('StackStorm') under one or more
  # contributor license agreements.  See the NOTICE file distributed with
  # this work for additional information regarding copyright ownership.
  # The ASF licenses this file to You under the Apache License, Version 2.0
  # (the "License"); you may not use this file except in compliance with
  # the License.  You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  from stevedore.driver import DriverManager
  from stevedore.extension import ExtensionManager
  
  from st2common import config
  config.parse_args()
  
  manager = ExtensionManager(namespace='st2common.runners.runner', invoke_on_load=False)
  extension_names = manager.names()
  
  print('Available / installed action runners:')
  for name in extension_names:
      manager = DriverManager(namespace='st2common.runners.runner', invoke_on_load=False,
                              name=name)
      runner_instance = manager.driver.get_runner()
      runner_metadata = manager.driver.get_metadata()[0]
  
      print('- %s (runner_module=%s,cls=%s)' % (name, runner_metadata['runner_module'],
                                                runner_instance.__class__))
  
subject: Add script for listing available / installed action runners.