title: What is "Pure Python?"
body: <p>Many questions on Stack Overflow refer to &quot;<em>Pure Python</em>&quot; (some random examples from the &quot;similar questions&quot; list: <a href="https://stackoverflow.com/q/3481779/4720018">1</a>, <a href="https://stackoverflow.com/q/3498839/4720018">2</a>, <a href="https://stackoverflow.com/q/138502/4720018">3</a>, <a href="https://stackoverflow.com/q/2939678/4720018">4</a>, <a href="https://stackoverflow.com/q/39278042/4720018">5</a>, <a href="https://stackoverflow.com/q/23016462/4720018">6</a>, <a href="https://stackoverflow.com/q/18557438/4720018">7</a>, <a href="https://stackoverflow.com/q/28724610/4720018">8</a>,
  <a href="https://stackoverflow.com/q/2486348/4720018">9</a>,
  <a href="https://stackoverflow.com/q/4059201/4720018">10</a>,
  <a href="https://stackoverflow.com/a/31384640">11</a>).</p>
  <p>I also encounter the concept elsewhere on the web, e.g. in the package documentation for <a href="https://imageio.github.io/" rel="nofollow noreferrer">imageio</a> and in tutorials such as <a href="http://python4esac.github.io/pure_python/pure_python.html" rel="nofollow noreferrer">&quot;An introduction to Pure Python&quot;</a>.</p>
  <p>This has led me to believe there must be some <em>universally accepted standard</em> definition of what &quot;<em>Pure Python</em>&quot; is.</p>
  <p>However, despite googling to the limits of my ability, I have not yet been able to locate this definition.</p>
  <p>Is there a universally accepted definition of &quot;Pure Python,&quot; or is this just some elusive concept that means different things to different people?</p>
  <p>To be clear, I am asking: Does such a definition exist, yes or no, and if so, what is the acclaimed source? Although I truly appreciate all comments and answers, I am not looking for personal interpretations.</p>