def test_restore(self):
patcher = StandardStreams(self.sys)
patcher.switch()
self.sys.stdout.write('out')
self.sys.stderr.write('err')
mock = patcher.restore()
self.assertEqual('outerr', mock.getvalue())
patcher.close()
self.assertEqual('', self.sys.stdout.getvalue())
self.assertEqual('', self.sys.stderr.getvalue())
