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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 _silence():
 """A context manager that silences sys.stdout and sys.stderr."""


    old_stdout = sys.stdout
    old_stderr = sys.stderr
    sys.stdout = _DummyFile()
    sys.stderr = _DummyFile()
    exception_occurred = False
    try:
        yield
    except:
        exception_occurred = True
        # Go ahead and clean up so that exception handling can work normally
        sys.stdout = old_stdout
        sys.stderr = old_stderr
        raise

    if not exception_occurred:
        sys.stdout = old_stdout
        sys.stderr = old_stderr