def test_value(self):
        """
        The value of the L{FlagConstant} which results from C{|} has all of the
        bits set which were set in either of the values of the two original
        constants.
        """
        flag = self.FXF.READ | self.FXF.WRITE
        self.assertEqual(
            self.FXF.READ.value | self.FXF.WRITE.value, flag.value
        )

        The value of the L{FlagConstant} which results from C{|} has all of the
        bits set which were set in either of the values of the two original
        constants.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/test/test_constants.py