title: Code Repository - What exactly is CTX in pyspark for a code repo?
body: <p>I have seen the use of ctx in a code repo, what exactly is this? Is it a built in library? When would I use it?</p>
  <p>I've seen it in examples such as the following:</p>
  <pre><code>df = ctx.spark.createdataframe(...
  </code></pre>