Printing a file and configure printer settings

Look at the "How To Print" page on Tim Golden's website. This page was the same in 2014 when you asked your question. There's an example printing a JPG file that also manipulates the printer settings.

That's not quite a perfect example for what you're doing but it should get you on the right track.

DC_PAPERS is defined in win32con:

import win32con
x = win32con.DC_PAPERS

How you're supposed to know that, I have no idea. Perhaps it's "obvious" to those already familiar with the Win32API outside of Python...