java.lang.NullPointerException
at org.apache.spark.sql.catalyst.expressions.GeneratedClass$SpecificMutableProjection.apply(Unknown Source)
at org.apache.spark.sql.execution.python.EvalPythonExec.$anonfun$doExecute$10(EvalPythonExec.scala:126)
at scala.collection.Iterator$$anon$10.next(Iterator.scala:461)
at scala.collection.Iterator$$anon$10.next(Iterator.scala:461)
at scala.collection.Iterator$GroupedIterator.takeDestructively(Iterator.scala:1161)
at scala.collection.Iterator$GroupedIterator.go(Iterator.scala:1176)
at scala.collection.Iterator$GroupedIterator.fill(Iterator.scala:1213)