How to read the total sessions of a connected service of a PricePlan

In WIX, when you create a PricePlan, you can connected existing BookingServices to the plan and select the number of sessions. Please refer to the attached screenshot.

Could I know how to write velo code to read the number of sessions of a certain connected service of a given PricePlan, i.e. the number highlighed on the attached screenshot.

I have read all the relevant content on WIX online document (see the url link below), but still get no answers.

https://www.wix.com/velo/reference/wix-pricing-plans-backend