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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 _add_stage(self, name):
 """ Add stage methods at runtime. Stage methods all follow the same pattern. :param name: Stage name. """

        def stage_func(self, *args, **kwargs):
            """ Stage function.

            :param args: Positional arguments.
            :param kwargs: Keyword arguments.
            :return: Pipeline (for method chaining).
            """
            self._pipe.append(Stage(name, args, kwargs))
            return self

        setattr(Pipeline, name, stage_func)