title: pyspark worker log to file or console
body: <p>any one knows how to log from a pyspark worker to either console or file? I set</p>
  
  <p>logging.basicConfig(filename='/var/log/pyspark.log', level=logging.INFO)</p>
  
  <p>but it has no effect. no such file is created, and no message showed up in console. </p>