The popup_get_file Version of Add GUI to Front-End of Script

Why recreate the wheel? There's a Popup function that will get a Filename for you. This is a single-line GUI:

fname = sg.popup_get_file('Document to open')

Shows this window and returns the results from the user interaction with it.

The entire Popup based solution for this get filename example is:

import PySimpleGUI as sg
import sys

if len(sys.argv) == 1:
    fname = sg.popup_get_file('Document to open')
else:
    fname = sys.argv[1]

if not fname:
    sg.popup("Cancel", "No filename supplied")
    raise SystemExit("Cancelling: no filename supplied")
else:
    sg.popup('The filename you chose was', fname)

How about a GUI and traditional CLI argument in 1 line of code?

import PySimpleGUI as sg
import sys

fname = sys.argv[1] if len(sys.argv) > 1 else sg.popup_get_file('Document to open')

if not fname:
    sg.popup("Cancel", "No filename supplied")
    raise SystemExit("Cancelling: no filename supplied")
else:
    sg.popup('The filename you chose was', fname)

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