mml=<math xmlns="http://www.w3.org/1998/Math/MathML"><mstyle mathsize="12px"><mrow><mfenced open="|" close="|"><mrow><mi mathvariant="normal">z</mi><mo> </mo><mo>-</mo><mo> </mo><mn>4</mn></mrow></mfenced><mo><</mo><mfenced open="|" close="|"><mrow><mi mathvariant="normal">z</mi><mo>-</mo><mn>2</mn></mrow></mfenced></mrow></mstyle></math>