How to get the number of members of a facebook group using the Facebook SDK Python?

Question

Python

Greetings. I'm learning python and asking for help in mastering the Facebook SDK for Python library. How can I get data on the number of group members using this library?
It turned out to pull out the list of participants using this query

i = graph.get_object(id="group_id", fields="members")

But this way I get a dictionary that is inconvenient to handle. I found the 'fan_count' method in the documentation, but it only applies to pages. Are there really no methods for getting the number of group members .. Or did I look badly?