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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_subparsers(self):
 """Recursively get subparsers."""


    subparsers = []
    for action in self._actions:
      if isinstance(action, argparse._SubParsersAction):
        for _, subparser in action.choices.items():
          subparsers.append(subparser)

    ret = subparsers
    for sp in subparsers:
      ret += sp._get_subparsers()
    return ret