Traceback (most recent call last):
  File "/usr/bin/fix_khmer_and_lao_coverage.py", line 90, in <module>
    main(sys.argv)
  File "/usr/bin/fix_khmer_and_lao_coverage.py", line 71, in main
    needed_chars = set(opentype_data.SPECIAL_CHARACTERS_NEEDED[script])
                                                               ^^^^^^
UnboundLocalError: cannot access local variable 'script' where it is not associated with a value