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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 do_notebook(self, name):
 """Run a notebook file after optionally converting it to a python file."""

        CONVERT_NOTEBOOKS = int(os.getenv('CONVERT_NOTEBOOKS', True))
        s = StringIO()
        if mock:
            out = unittest.mock.patch('sys.stdout', new=MockDevice(s))
            err = unittest.mock.patch('sys.stderr', new=MockDevice(s))
            self._do_notebook(name, CONVERT_NOTEBOOKS)
            out.close()
            err.close()
        else:
            self._do_notebook(name, CONVERT_NOTEBOOKS)
        self.assertTrue(True)