def add_role name
      if allowed_role? name
        return if has_role? name
        role = Role.find_by(name: name.to_s)
        roles << role
      end
    end
def add_role name
      if allowed_role? name
        return if has_role? name
        role = Role.find_by(name: name.to_s)
        roles << role
      end
    end
These methods are included in all User instances