Any word with generic Nahuatl language will raise exception #54
Description
Language code for Nahuatl is missing.
print(ety.tree('avocado'))
Will raise an exception:
"Language with iso code 'nah' unknown"
ISO 639 specifies it:
https://en.wikipedia.org/wiki/Template:ISO_639_name_nah
Recommend adding it to data/iso-639-3.json
btw thank you! awesome work!