How to use the dsub.providers.google_v2_pipelines.build_action function in dsub

script_var=_SCRIPT_VARNAME,
        python_decode_script=_PYTHON_DECODE_SCRIPT,
        script_path=script_path,
        mk_io_dirs=_MK_IO_DIRS)

    prepare_env = self._get_prepare_env(script, task_view, inputs, outputs,
                                        mounts)
    localization_env = self._get_localization_env(inputs, user_project)
    user_environment = self._build_user_environment(envs, inputs, outputs,
                                                    mounts)
    delocalization_env = self._get_delocalization_env(outputs, user_project)

    # Build the list of actions
    actions = []
    actions.append(
        google_v2_pipelines.build_action(
            name='logging',
            flags='RUN_IN_BACKGROUND',
            image_uri=_CLOUD_SDK_IMAGE,
            environment=logging_env,
            entrypoint='/bin/bash',
            commands=['-c', continuous_logging_cmd]))

    if job_resources.ssh:
      actions.append(
          google_v2_pipelines.build_action(
              name='ssh',
              image_uri=_SSH_IMAGE,
              mounts=[mnt_datadisk],
              entrypoint='ssh-server',
              port_mappings={_DEFAULT_SSH_PORT: _DEFAULT_SSH_PORT},
              flags='RUN_IN_BACKGROUND'))

]),
        google_v2_pipelines.build_action(
            name='delocalization',
            image_uri=_CLOUD_SDK_IMAGE,
            mounts=[mnt_datadisk],
            environment=delocalization_env,
            entrypoint='/bin/bash',
            commands=[
                '-c',
                _LOCALIZATION_CMD.format(
                    log_msg_fn=_LOG_MSG_FN,
                    recursive_cp_fn=_GSUTIL_RSYNC_FN,
                    cp_fn=_GSUTIL_CP_FN,
                    cp_loop=_DELOCALIZATION_LOOP)
            ]),
        google_v2_pipelines.build_action(
            name='final_logging',
            flags='ALWAYS_RUN',
            image_uri=_CLOUD_SDK_IMAGE,
            environment=logging_env,
            entrypoint='/bin/bash',
            commands=['-c', logging_cmd]),
    ])

    assert len(actions) - 2 == user_action
    assert len(actions) == final_logging_action

    # Prepare the VM (resources) configuration
    disks = [
        google_v2_pipelines.build_disk(
            _DATA_DISK_NAME,
            job_resources.disk_size,

def _get_mount_actions(self, mounts, mnt_datadisk):
    """Returns a list of two actions per gcs bucket to mount."""
    actions_to_add = []
    for mount in mounts:
      bucket = mount.value[len('gs://'):]
      mount_path = mount.docker_path
      actions_to_add.extend([
          google_v2_pipelines.build_action(
              name='mount-{}'.format(bucket),
              flags=['ENABLE_FUSE', 'RUN_IN_BACKGROUND'],
              image_uri=_GCSFUSE_IMAGE,
              mounts=[mnt_datadisk],
              commands=[
                  '--implicit-dirs', '--foreground', '-o ro', bucket,
                  os.path.join(providers_util.DATA_MOUNT_POINT, mount_path)
              ]),
          google_v2_pipelines.build_action(
              name='mount-wait-{}'.format(bucket),
              flags=['ENABLE_FUSE'],
              image_uri=_GCSFUSE_IMAGE,
              mounts=[mnt_datadisk],
              commands=[
                  'wait',
                  os.path.join(providers_util.DATA_MOUNT_POINT, mount_path)

environment=logging_env,
            entrypoint='/bin/bash',
            commands=['-c', continuous_logging_cmd]))

    if job_resources.ssh:
      actions.append(
          google_v2_pipelines.build_action(
              name='ssh',
              image_uri=_SSH_IMAGE,
              mounts=[mnt_datadisk],
              entrypoint='ssh-server',
              port_mappings={_DEFAULT_SSH_PORT: _DEFAULT_SSH_PORT},
              flags='RUN_IN_BACKGROUND'))

    actions.append(
        google_v2_pipelines.build_action(
            name='prepare',
            image_uri=_CLOUD_SDK_IMAGE,
            mounts=[mnt_datadisk],
            environment=prepare_env,
            entrypoint='/bin/bash',
            commands=['-c', prepare_command]),)

    actions.extend(mount_actions)

    actions.extend([
        google_v2_pipelines.build_action(
            name='localization',
            image_uri=_CLOUD_SDK_IMAGE,
            mounts=[mnt_datadisk],
            environment=localization_env,
            entrypoint='/bin/bash',

delocalization_env = self._get_delocalization_env(outputs, user_project)

    # Build the list of actions
    actions = []
    actions.append(
        google_v2_pipelines.build_action(
            name='logging',
            flags='RUN_IN_BACKGROUND',
            image_uri=_CLOUD_SDK_IMAGE,
            environment=logging_env,
            entrypoint='/bin/bash',
            commands=['-c', continuous_logging_cmd]))

    if job_resources.ssh:
      actions.append(
          google_v2_pipelines.build_action(
              name='ssh',
              image_uri=_SSH_IMAGE,
              mounts=[mnt_datadisk],
              entrypoint='ssh-server',
              port_mappings={_DEFAULT_SSH_PORT: _DEFAULT_SSH_PORT},
              flags='RUN_IN_BACKGROUND'))

    actions.append(
        google_v2_pipelines.build_action(
            name='prepare',
            image_uri=_CLOUD_SDK_IMAGE,
            mounts=[mnt_datadisk],
            environment=prepare_env,
            entrypoint='/bin/bash',
            commands=['-c', prepare_command]),)

cp_loop=_LOCALIZATION_LOOP)
            ]),
        google_v2_pipelines.build_action(
            name='user-command',
            image_uri=job_resources.image,
            mounts=[mnt_datadisk] + persistent_disk_mounts,
            environment=user_environment,
            entrypoint='/usr/bin/env',
            commands=[
                'bash', '-c',
                _USER_CMD.format(
                    tmp_dir=providers_util.TMP_DIR,
                    working_dir=providers_util.WORKING_DIR,
                    user_script=script_path)
            ]),
        google_v2_pipelines.build_action(
            name='delocalization',
            image_uri=_CLOUD_SDK_IMAGE,
            mounts=[mnt_datadisk],
            environment=delocalization_env,
            entrypoint='/bin/bash',
            commands=[
                '-c',
                _LOCALIZATION_CMD.format(
                    log_msg_fn=_LOG_MSG_FN,
                    recursive_cp_fn=_GSUTIL_RSYNC_FN,
                    cp_fn=_GSUTIL_CP_FN,
                    cp_loop=_DELOCALIZATION_LOOP)
            ]),
        google_v2_pipelines.build_action(
            name='final_logging',
            flags='ALWAYS_RUN',