Data sources zero suppression with complex expression

I have a csv file that has two columns one for Debits and the other for Credits columns E and F (5 and 6). 

I'm using the code to take the Debit column if there is a number in Col E use it, if zero, take number from Col F instead.

In the Data Sources settings in order for the script to work properly I need zero suppression to be False or it won't pick up the credit column. Note in the script that integer = 5 is referring to column 6.

Is there a way to suppress zero after the script runs or write zero suppress into the script? 

Thanks Scott