def member_of?(group)
      if group.is_a? Group
        groups.include? group
      else
        member_of? Group.new(group)
      end
    end
def member_of?(group)
      if group.is_a? Group
        groups.include? group
      else
        member_of? Group.new(group)
      end
    end
Is the user associated with the auth context a member of the group?
 @param group [Group, String] group object or group id
 @return [Boolean]