title: Spark DataFrame from SequenceFile
body: <pre><code>sqlContext.read.format('orc').load(hdfspath)
  sqlContext.read.format('parquet').load(hdfspath)
  </code></pre>
  
  <p>This works fine</p>
  
  <pre><code>sqlContext.read.format('sequencefile').load(hdfspath)
  </code></pre>
  
  <p>But sequencefile format does not work like that.</p>
  
  <p>How can I read a sequence file as a dataframe in PySpark?</p>