You don't need to "call" a DAL. (It’s like a library, but the functions declared are executed automatically.)
The functions you see when creating a new DAL script are called “hooks”. Hooks are not called manually in a function. They are called automatically (“in the background”) when you update or create a dataset of a given table.
So, if you want to update a dataset in a print session (like mark a set as printed), you need to modify the dataset. To invoke DAL hooks, you need to use the correct standard functions:
This will call the defined hooks of the table on runtime.