title: Submit a PySpark job to a cluster with the '--py-files' argument
body: <p>I was trying to submit a job with the the GCS uri of the zip of the python files to use (via the --py-files argument) and the python file name as the PY_FILE argument value.
  This did not seem to work. Do I need to provide some relative path for the PY_FILE value? The PY_FILE is also included in the zip.
  e.g. in</p>
  
  <pre><code>gcloud beta dataproc jobs submit pyspark  --cluster clustername --py-files gcsuriofzip PY_FILE    
  </code></pre>
  
  <p>what should the value of PY_FILE be?</p>