I am relatively new to NiFi and am not sure how to do the following correctly. I would like to use ExecuteScript processor (script engine: python) to do the following (only in python please): 1) There is a CSV file containing the following information (the first row is the header): first,second,third 1,4,9 7,5,2 3,8,7 2) I would like to find the sum of individual rows and generate a final file with a modified header. The final file should look like this: first,second,third,total 1,4,9,14 7,5,2,14 3,8,7,18 For the python script, I wrote: def summation(first,second,third): numbers = first + second + third return numbers flowFile = session.get() if (flowFile != None): flowFile = session.write(flowFile, summation()) But it does not work and I am not sure how to fix this. Can anyone provide me an understanding on how to approach this problem? The NiFi flow: ... View more