Note: This was originally posted by an inactive account. Content was preserved by moving under an admin account.
I can think of a couple of ways to at least help you out, but it's not exactly what you're asking.
- Create a library node with the function in it and just use this where needed.
- This is a little messy but if you don't want to create too many library nodes you could create a Data Flow Parameter of type text (let's say name it PyFunction) and enter your function there. Then when you start a new Transform node in ConfigureFields you just need to put in {{^PyFunction^}} and it will be the equivalent of copying and pasting it to every Transform node.