def METHOD_NAME(self, mock_check_call):
    cmdline = 'ecs execute-command --cluster someCluster ' \
              '--task someTaskId ' \
              '--interactive --command ls ' \
              '--region us-west-2'
    mock_check_call.side_effect = OSError(errno.ENOENT, 'some error')
    self.run_cmd(cmdline, expected_rc=255)