old_contents: #!/usr/bin/env bash
  
  ###############################################################################
  # Copyright 2018 The Apollo Authors. All Rights Reserved.
  #
  # Licensed 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.
  ###############################################################################
  
  DEMO_BAG_URL = "https://github.com/ApolloAuto/apollo/releases/download/v2.5.0/demo_2.5.bag"
  
  import urllib
  import os
  
  URL_LIST = [
      "https://github.com/ApolloAuto/apollo/releases/download/v1.5.0/demo_1.5.bag",
      "https://github.com/ApolloAuto/apollo/releases/download/v2.0.0/demo_2.0.bag",
      "https://github.com/ApolloAuto/apollo/releases/download/v2.0.0/apollo_2.0_camera_sample.bag",
      "https://github.com/ApolloAuto/apollo/releases/download/v2.5.0/demo_2.5.bag",
      "https://github.com/ApolloAuto/apollo/releases/download/v1.0.0/demo_1.0.bag",
  ]
  
  URL_DICT = {}
  for link in URL_LIST:
      name = link.split("/")[-1]
      URL_DICT[name] = link
  
  
  def retrieve_rosbag(bagname):
      if bagname not in URL_DICT:
          print(
              "bag[%s] is unknown, use one of the following rosbag names:\n%s" %
              (bagname, ", ".join([name for name in URL_DICT.keys()])))
          return False
      url = URL_DICT[bagname]
      print("Downloading from %s" % url)
      ret = os.system('wget %s -O %s' % (url, bagname))
      return ret == 0
  
  
  if __name__ == "__main__":
      import argparse
      parser = argparse.ArgumentParser(
          description='retrieve demo rosbag file from remote')
      parser.add_argument(
          'name',
          type=str,
          help='rosbag names. You can choose one of [%s]' % ", ".join(
              [name for name in URL_DICT.keys()]))
      args = parser.parse_args()
      if retrieve_rosbag(args.name):
          print("Download %s success" % args.name)
      else:
          print("Download %s failed" % args.name)
  
new_contents: #!/usr/bin/env bash
  
  ###############################################################################
  # Copyright 2018 The Apollo Authors. All Rights Reserved.
  #
  # Licensed 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.
  ###############################################################################
  
  
  import urllib
  import os
  
  URL_LIST = [
      "https://github.com/ApolloAuto/apollo/releases/download/v1.5.0/demo_1.5.bag",
      "https://github.com/ApolloAuto/apollo/releases/download/v2.0.0/demo_2.0.bag",
      "https://github.com/ApolloAuto/apollo/releases/download/v2.0.0/apollo_2.0_camera_sample.bag",
      "https://github.com/ApolloAuto/apollo/releases/download/v2.5.0/demo_2.5.bag",
      "https://github.com/ApolloAuto/apollo/releases/download/v1.0.0/demo_1.0.bag",
  ]
  
  URL_DICT = {}
  for link in URL_LIST:
      name = link.split("/")[-1]
      URL_DICT[name] = link
  
  
  def retrieve_rosbag(bagname):
      if bagname not in URL_DICT:
          print(
              "bag[%s] is unknown, use one of the following rosbag names:\n%s" %
              (bagname, ", ".join([name for name in URL_DICT.keys()])))
          return False
      url = URL_DICT[bagname]
      print("Downloading from %s" % url)
      ret = os.system('wget %s -O %s' % (url, bagname))
      return ret == 0
  
  
  if __name__ == "__main__":
      import argparse
      parser = argparse.ArgumentParser(
          description='retrieve demo rosbag file from remote')
      parser.add_argument(
          'name',
          type=str,
          help='rosbag names. You can choose one of [%s]' % ", ".join(
              [name for name in URL_DICT.keys()]))
      args = parser.parse_args()
      if retrieve_rosbag(args.name):
          print("Download %s success" % args.name)
      else:
          print("Download %s failed" % args.name)
  
subject: Remove useless variable DEMO_BAG_URL