code: def get_subparser(self, name):
          
          if self._subparsers_action is None:
              raise ValueError("%s has no subparsers defined!" % self)
          return self._subparsers_action.choices[name]
docs: Convenience method to get a certain subparser
  
          Parameters
          ----------
          name: str
              The name of the subparser
  
          Returns
          -------
          FuncArgParser
              The subparsers corresponding to `name`