'If more than one constant is associated with a particular value,
L{Flags.lookupByValue} returns whichever of them is defined first.'

def test_lookupDuplicateByValue(self):

    class TIMEX(Flags, ):
        ADJ_OFFSET = FlagConstant(1)
        MOD_OFFSET = FlagConstant(1)
    self.assertIs(TIMEX.lookupByValue(1), TIMEX.ADJ_OFFSET)
