I forgot to mention that you need to split your data file by line first. c=csv.split("\n" )
If your platform is Windows, You can run the Powershell command in a SysCommand node.
e.g. - read inputfile.csv and write to outputfile.csv with header record = "a,b,c,d,e" and sort by c as [int]
We are on MT. We decided to sort and summarize outside of IPA using PL/SQL and trigger the flow via a File Channel to load the JEs into CSF.