'A L{FlagConstant} instance which results from C{|} can be
iterated upon to yield the original constants.'

def test_iterate(self):

    self.assertEqual(set((self.FXF.WRITE & self.FXF.READ)), set(()))
    self.assertEqual(set(self.FXF.WRITE), set((self.FXF.WRITE,)))
    self.assertEqual(set((self.FXF.WRITE | self.FXF.EXCLUSIVE)), set((self.FXF.WRITE, self.FXF.EXCLUSIVE)))
