Command Line Parameters extension (without breaking stdin) about md2pptx HOT 2 CLOSED

if len(sys.argv) > 2:
    # Have input file as well as output file
    input_filename = sys.argv[1]
    output_filename = sys.argv[2]
    
    if Path(input_filename).exists():
        input_path = Path(input_filename)
        with input_path.open() as file:
            input_file = file.readlines()
    else:
        print('Input file specified but does not exist. Terminating.')
elif len(sys.argv) == 1:
    print("No parameters. Terminating")
    sys.exit()
else:
    output_filename = sys.argv[1]

    input_file = sys.stdin.readlines()

if len(input_file) == 0:
    print("Empty input file. Terminating")
    sys.exit()