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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 result(self):
 """The result method which returns a context manager Returns: ContextManager: The corresponding context manager """

        if self.exception():
            raise self.exception()
        # Otherwise return a context manager that cleans up after the block.

        @contextlib.contextmanager
        def f():
            try:
                yield self._wrapped.result()
            finally:
                self._exit_callback()
        return f()