title: Installing pyspark on hadoop and yarn
body: <p>I have installed spark on top of <code>hadoop</code> and <code>yarn</code>.
  when I launch the <code>pyspark shell</code> and try to compute something I get this error.</p>
  
  <pre><code>Error from python worker:
    /usr/bin/python: No module named pyspark
  </code></pre>
  
  <p>The <code>pyspark</code> module should be there, do I have to put an external link to it?</p>