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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 _remove_os_link():
 """ In a context, remove and restore os.link if it exists """


        class NoValue:
            pass

        orig_val = getattr(os, 'link', NoValue)
        try:
            del os.link
        except Exception:
            pass
        try:
            yield
        finally:
            if orig_val is not NoValue:
                setattr(os, 'link', orig_val)