$ ./make_tileset.py -h
$ python3 make_tileset.py -h
usage: make_tileset.py [-h] --height HEIGHT [--width WIDTH] [-o OUT] input_file

positional arguments:
  input_file         A truetype (.ttf) font file.

options:
  -h, --help         show this help message and exit
  --height HEIGHT    Height of each glyph (bounding box) in pixels.
  --width WIDTH      Width of each glyph (bounding box) in pixels. (Optional)
  -o OUT, --out OUT  The output file. (Defaults to .png)

python make_tileset.py Px437_IBM_Model3x_Alt3.ttf --width 8 --height 16