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	<li>Item 1</li>
	<li>Item 2</li>
	<li>Item 3</li>
	<li>Item 4</li>
	<li id="find-me">Item 5</li>
	<li>Item 6</li>
	<li>Item 7</li>
	<li>Item 8</li>
	<li>Item 9</li>




                const target = document.getElementById('find-me');
const getSiblings = elem => {
  // 因為 elem.parentNode 不是真的陣列,只是 Array-like,因此不能直接使用 Array 的方法
  // 若我們不想先透過 Array.from() 把它轉成陣列,
  // 而是希望直接代到 filter 中使用的話,可以透過 .call() 來達成
  // 等同於 elem.parentNode.children.filter(...)
  return, sibling => {
    return sibling !== elem