How can I find out if a user is in a Facebook group?

Question

PHP

Hello!
The task before me is to consider whether a person has joined a group or whether he is a member of it.
collback widget does not allow (or rather, I did not find such a function) to find out the result of the entry, is there any other way to find out?
PS I received the token, is it possible to come up with a check with it?