# File lib/sqs/right_sqs.rb, line 197
      def pop
        list = @sqs.interface.pop_messages(@url, 1)
        return nil if list.empty?
        entry = list[0]
        msg = Message.new(self, entry['MessageId'], entry['ReceiptHandle'],
                            entry['Body'], visibility)
        msg.received_at = Time.now
        msg.receive_checksum = entry['MD5OfBody']
        msg
      end