[NTG-context] How to load a lua file into a named lua instance

Hi all, I have a module with lots of lua code, and I'd like to move most of the lua code to a separate file, say t-module.lua. I have written all of the lua code using \modulecode and \startmodulecode ... \stopmodulecode. But, when I move the lua code to t-module.lua and load it with dofile, it seems to load in the global instance instead of the third party module instance. Is there any method to load an external lua file in a named instance? Thanks, Kevin