def test_headerSeparation(self):
        req = FakeRequest()
        req.setHeader('foo', 'bar')
        self.assertFalse(req.requestHeaders.hasHeader('foo'))
        self.assertEqual(req.getHeader('foo'), None)
        req.requestHeaders.setRawHeaders('foo', ['bar'])
        self.assertEqual(req.getHeader('foo'), 'bar')
Verify MLT with the tag field.
dataset/ETHPy150Open twisted/nevow/nevow/test/test_testutil.py/TestFakeRequest.test_headerSeparation--crossover with--dataset/ETHPy150Open mozilla/elasticutils/elasticutils/tests/test_mlt.py/MoreLikeThisTest.test_mlt_on_tag