code: def wait_for_command_termination(self):
      self._command_thread.join()
  
imports: import abc
  import threading
  from horovod.runner.common import util
  from horovod.runner.common.util import network, safe_shell_exec, timeout
  from horovod.runner.util.streams import Pipe
  from horovod.runner.util.threads import in_thread
label_desc: Use image node_id 9 for calling the BasicTaskService obj's underlying member method code with example usage: obj.wait_for_command_termination() without return types