How can I debug silent failure - print no output

[Michael Torrie]

On 05/27/2016 08:41 PM, Sayth Renshaw wrote:
> This is my terminal and directory structure.

Add more print() calls. Offhand I'd say that pq(filename=filename) is
returning an empty list so that for loop is not doing anything.  Hence
your debugging print() calls never happen.

Add sanity print()'s earlier in your program, and make sure everything
you are iterating over is what you expect.