# File lib/fog/aws/models/iam/role.rb, line 23
        def attach(policy_or_arn)
          requires :rolename

          arn = if policy_or_arn.respond_to?(:arn)
                  policy_or_arn.arn
                else
                  policy_or_arn
                end

          service.attach_role_policy(self.rolename, arn)
        end