def group_list(user_id, sort = "my_activity")
      data = request("/group/list", id: user_id, sort: sort)
      Hashie::Mash.new(data["groups"]["list"])
    end
def group_list(user_id, sort = "my_activity")
      data = request("/group/list", id: user_id, sort: sort)
      Hashie::Mash.new(data["groups"]["list"])
    end
Get list of groups a given user is a member of