title: pyspark : How to write dataframe partition by year/month/day/hour sub-directory?
body: <p>I have tab delimited data(csv file) like below:</p>
  
  <pre><code>201911240130 a
  201911250132 b
  201911250143 c
  201911250223 z
  201911250224 d
  ...
  </code></pre>
  
  <p>I want to write directory group by year, month, day, hour. </p>
  
  <pre><code>hdfs://dest/2019/11/24/01/xxxx.csv
  hdfs://dest/2019/11/25/01/xxxx.csv
  hdfs://dest/2019/11/25/02/xxxx.csv
  </code></pre>
  
  <p>How can I write partition by yyyy/mm/dd/hh?</p>