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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 unredirect_stdout(self):
 """Redirect stdout and stderr back to screen."""

        if hasattr(self, 'hijacked_stdout') and hasattr(self, 'hijacked_stderr'):
            sys.stdout = self.hijacked_stdout
            sys.stderr = self.hijacked_stderr