<<< native
[ EDelimited
    "|"
    "|"
    [ Right (EOver False (EIdentifier "z") (ESymbol Accent "\8254")) ]
, ESymbol Rel "="
, EDelimited "|" "|" [ Right (EIdentifier "z") ]
, ESymbol Pun ","
, EDelimited
    "|"
    "|"
    [ Right
        (ESuper
           (EDelimited
              "("
              ")"
              [ Right (EOver False (EIdentifier "z") (ESymbol Accent "\8254")) ])
           (EIdentifier "n"))
    ]
, ESymbol Rel "="
, ESuper
    (EDelimited "|" "|" [ Right (EIdentifier "z") ]) (EIdentifier "n")
, ESymbol Pun ","
, EMathOperator "arg"
, EDelimited
    "(" ")" [ Right (ESuper (EIdentifier "z") (EIdentifier "n")) ]
, ESymbol Rel "="
, EIdentifier "n"
, EMathOperator "arg"
, EDelimited "(" ")" [ Right (EIdentifier "z") ]
]
>>> mml
<?xml version='1.0' ?>
<math display="block" xmlns="http://www.w3.org/1998/Math/MathML">
  <mrow>
    <mrow>
      <mo stretchy="true" form="prefix">|</mo>
      <mover>
        <mi>z</mi>
        <mo accent="true">‾</mo>
      </mover>
      <mo stretchy="true" form="postfix">|</mo>
    </mrow>
    <mo>=</mo>
    <mrow>
      <mo stretchy="true" form="prefix">|</mo>
      <mi>z</mi>
      <mo stretchy="true" form="postfix">|</mo>
    </mrow>
    <mo>,</mo>
    <mrow>
      <mo stretchy="true" form="prefix">|</mo>
      <msup>
        <mrow>
          <mo stretchy="true" form="prefix">(</mo>
          <mover>
            <mi>z</mi>
            <mo accent="true">‾</mo>
          </mover>
          <mo stretchy="true" form="postfix">)</mo>
        </mrow>
        <mi>n</mi>
      </msup>
      <mo stretchy="true" form="postfix">|</mo>
    </mrow>
    <mo>=</mo>
    <msup>
      <mrow>
        <mo stretchy="true" form="prefix">|</mo>
        <mi>z</mi>
        <mo stretchy="true" form="postfix">|</mo>
      </mrow>
      <mi>n</mi>
    </msup>
    <mo>,</mo>
    <mo>arg</mo>
    <mrow>
      <mo stretchy="true" form="prefix">(</mo>
      <msup>
        <mi>z</mi>
        <mi>n</mi>
      </msup>
      <mo stretchy="true" form="postfix">)</mo>
    </mrow>
    <mo>=</mo>
    <mi>n</mi>
    <mo>arg</mo>
    <mrow>
      <mo stretchy="true" form="prefix">(</mo>
      <mi>z</mi>
      <mo stretchy="true" form="postfix">)</mo>
    </mrow>
  </mrow>
</math>