Support Request regarding FHIR Extensions (Bachelor Thesis)

Dear InterSystems-Maintainer Team,

I am currently conducting a comparative evaluation of FHIR clients as part of my
bachelor thesis in health informatics. One of my evaluation criteria is the response
time to support inquiries.

Therefore, I would like to kindly ask the following question as part of my analysis:
How can I read and write custom FHIR extensions using your client library?

If available, could you point me to any documentation or examples?

Many thanks for your time and support!

Kind regards,
Rüya Gökoglu