Traceback (most recent call last):
  File "/usr/bin/generate_sample_text.py", line 49, in <module>
    main(sys.argv)
    ~~~~^^^^^^^^^^
  File "/usr/bin/generate_sample_text.py", line 36, in main
    code1 = char_rep_to_code(arg[:hyphen_index])
  File "/usr/bin/generate_sample_text.py", line 27, in char_rep_to_code
    return int(char_rep, 16)
ValueError: invalid literal for int() with base 16: ''