[Question] How to use `*_qgram` packages?

[carschno]

As documented, Abydos comes with a number of installable packages. I am particularly intrigued by the qgram packages for various languages:

abydos.util.list_available_packages()
[...]
('qgram_corpora',
   'Q-Gram corpora',                                                                                 
   ['de_qgram',
    'en_GB_qgram',                                                                                   
    'en_qgram',
    'en_US_qgram',                                                                                   
    'es_qgram',
    'fr_qgram',                                                                                      
    'he_qgram',
    'it_qgram',     
    'ru_qgram',  
    'wikitext_qgram',                                                                                
    'zh_CN_qgram'])])

I expect that these are qgram representations for the words/tokens in the given language. However, it is unclear to me, how to use them, e.g. for matching an input string against the qgram representations.

Could you point me to the relevant part in the documents, or point out how it works?
In order to turn this into an issue: once I understand how this works, I would be happy to create a PR for updating the documentation accordingly, if needed.