Consider hypenated words as whole word

[Arthur]

Hello,

I have the word "add-ons" in a file and Pyenchant reports the "ons" word as unknown.
I have added "add-ons" in my personal word list, but it does not help. For me to fix the error, I have to add "ons" in my word list... Which is not good.

What am I missing? How to force Pyenchant to see hyphenated words as one word?

Thanks for any help!