title: Is a Python list guaranteed to have its elements stay in the order they are inserted in?
body: <p>If I have the following Python code</p>
  
  <pre><code>&gt;&gt;&gt; x = []
  &gt;&gt;&gt; x = x + [1]
  &gt;&gt;&gt; x = x + [2]
  &gt;&gt;&gt; x = x + [3]
  &gt;&gt;&gt; x
  [1, 2, 3]
  </code></pre>
  
  <p>Will <code>x</code> be guaranteed to always be <code>[1,2,3]</code>, or are other orderings of the interim elements possible?</p>