'A L{Headers} instance compares equal to itself and to another
L{Headers} instance with the same values.'

def test_headersComparison(self):

    first = Headers()
    first.setRawHeaders(u'foo\xe1', [u'panda'])
    second = Headers()
    second.setRawHeaders(u'foo\xe1', [u'panda'])
    third = Headers()
    third.setRawHeaders(u'foo\xe1', [u'lemur', u'panda'])
    self.assertEqual(first, first)
    self.assertEqual(first, second)
    self.assertNotEqual(first, third)
    firstBytes = Headers()
    firstBytes.setRawHeaders('foo\xe1', ['panda'])
    secondBytes = Headers()
    secondBytes.setRawHeaders('foo\xe1', ['panda'])
    thirdBytes = Headers()
    thirdBytes.setRawHeaders('foo\xe1', ['lemur', u'panda'])
    self.assertEqual(first, firstBytes)
    self.assertEqual(second, secondBytes)
    self.assertEqual(third, thirdBytes)
