Execute script on one text file, and create new text file with output without cmd

Title is pretty self-explanatory. Currently I have:

with open('dwarf_fort.txt') as f:
    for minerals in f:
        mining_rig()

I need it to go from 'dwarf_fort.txt', execute the program and append the output into a new file. What am I missing here? Thank you.

This should work:

with open('dwarf_fort.txt') as f, open('out_f.txt', mode='w') as f1:
    for minerals in f:
        f1.write(minerals)

If the output file is still blank, do some checks:

• Make sure the dwarf_fort.txt is in the same directory as the .py script.
• Make sure the dwarf_fort.txt is not blank
• Make sure your script is in a directory that is writeable to (so that the out_f.txt that gets created can be written to)