<pre class="shiki github-dark shaku"><code>/** * @param {any[]} arr * @returns {?} - sorry no type hint for this */function wrap(arr) { const normalizeProp = (prop, arrLength) =&gt; prop &gt;= 0 ? prop : prop + arrLength; const isNumber = (prop) =&gt; typeof prop !== 'symbol' &amp;&amp; !isNaN(prop); return new Proxy(arr, { get(target, prop, receiver) { if (isNumber(prop)) { prop = normalizeProp(+prop, target.length); } return Reflect.get(target, prop, receiver); }, set(target, prop, value, receiver) { if (isNumber(prop)) { prop = normalizeProp(+prop, target.length); } if (prop &lt; 0) throw new Error('Index is not valid'); return Reflect.set(target, prop, value, receiver); } })}</code></pre>

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Python supports negative list index , while JavaScript doesn't. Can you write a wrapper function to make negative array index possible? const original…