An exception occurs when using parseMath!The attribute "mathvariant" is incorrect!

[masx200]

<script src="https://cdn.jsdelivr.net/gh/asciimath/asciimathml@master/ASCIIMathML.min.js"></script>

console.log(asciimath.parseMath('sum_(i=1)^n i^3=((n(n+1))/2)^2'))

<math title="sum_(i=1)^n i^3=((n(n+1))/2)^2"><mstyle mathcolor="blue" fontsize="1em" mathsize="1em" fontfamily="serif" mathvariant="serif" displaystyle="true"><mi>s</mi><mi>u</mi><mi>m</mi><mo>_</mo><mo>(</mo><mi>i</mi><mo>=</mo><mn>1</mn><mo>)</mo><mo>^</mo><mi>n</mi><mi>i</mi><mo>^</mo><mn>3</mn><mo>=</mo><mo>(</mo><mo>(</mo><mi>n</mi><mo>(</mo><mi>n</mi><mo>+</mo><mn>1</mn><mo>)</mo><mo>)</mo><mo>/</mo><mn>2</mn><mo>)</mo><mo>^</mo><mn>2</mn></mstyle></math>

The attribute "mathvariant" is incorrect! "serif"

https://developer.mozilla.org/en-US/docs/Web/MathML/Element/mi

mathvariant This logical class of the identifier, which varies in typography. That is, although the names suggest the typographic style for the class, semantically, items with the same class are treated "the same" within an expression, which might or might not involve displaying them with the named typography. The following values are allowed: normal (Default value for more than one character) ; Example bold ; Example italic (Default value for a single character) ; Example bold-italic ; Example double-struck ; Example bold-fraktur ; Example script ; Example bold-script ; Example fraktur ; Example sans-serif ; Example bold-sans-serif ; Example sans-serif-italic ; Example sans-serif-bold-italic ; Example monospace ; Example initial ; مثال tailed ; مثال looped ; مثال stretched ; مثال

[masx200]

The way it transforms is obviously wrong!