Knowing even less about Tk than you profess to know, this is not an answer to the question asked, but rather a distinctly non-rhetorical question in reply:
Why are you using Tk merely to create a button?
It seems likely to me that executing this script is not significantly less demanding (of the ultimate user) than it would be to execute a non-GUI script from the command line.
Granted, when you write the code to populate your hashes (rather than hardcoding them), your CLI script will likely need argument(s) [source file(s) and output file] but if the Monks who can answer your actual question conclude that the issue is in some- or large-part the extra overhead of Tk, you're faced with a choice: "to take a hit in performance in exchange for the simple interface" or to offer the user(s) a usage prompt or training.