Simple script in FDMEE to use Apache POI fails in 11.2.15 and 11.2.16

Anyone have got an idea on how to get this to work in 11.2.15 and 11.2.16.
This exact script works fine in 11.2.13 that we were running. But after upgrade it doesn't work anymore.

# import Java and Apache POI classes
from java.io import FileOutputStream
from java.io import IOException
from org.apache.poi.xssf.usermodel import XSSFWorkbook
from org.apache.poi.xssf.usermodel import XSSFDataFormat
from org.apache.poi.xssf.streaming import SXSSFWorkbook
fdmAPI.logDebug("exportResultSetToFileJson - Creating the excel file")
#wb = XSSFWorkbook()
wb = SXSSFWorkbook(100) # keep 100 rows in memory, exceeding rows will be flushed to disk

ws = wb.createSheet("Export")

The error message returned is either (seems to alternate between them):