AWS supports the following Ruby runtimes:

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Name | Identifier | SDK for Ruby | Operating system
-- | -- | -- | --
Ruby 2.7 | ruby2.7 | 3.0.1 | Amazon Linux 2
Ruby 2.5 | ruby2.5 | 3.0.1 | Amazon Linux

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Currently, `localstack/lambda` only contains the `ruby2.5` tag. Will the 2.7 runtime be supported in the (near) future?
self.assertEqual(notification['Subject'], subject)
    def test_lambda_send_message_to_sqs(self):
        function_name = '{}-{}'.format(TEST_LAMBDA_FUNCTION_PREFIX, short_uid())
        queue_name = 'lambda-queue-{}'.format(short_uid())
        sqs_client = aws_stack.connect_to_service('sqs')
        testutil.create_lambda_function(handler_file=TEST_LAMBDA_SEND_MESSAGE_FILE,
                                        func_name=function_name,
                                        runtime=LAMBDA_RUNTIME_PYTHON36)
        queue_url = sqs_client.create_queue(QueueName=queue_name)['QueueUrl']
        event = {
            'message': 'message-from-test-lambda-{}'.format(short_uid()),
            'queue_name': queue_name,
            'region_name': config.DEFAULT_REGION
        }
        self.lambda_client.invoke(
            FunctionName=function_name,
            Payload=json.dumps(event)
        )
        
        def receive_message():
            rs = sqs_client.receive_message(QueueUrl=queue_url, MessageAttributeNames=['All'])
            self.assertGreater(len(rs['Messages']), 0)
            return rs['Messages'][0]
        message = retry(receive_message, retries=3, sleep=2)
        self.assertEqual(message['Body'], event['message'])
        
        testutil.delete_lambda_function(function_name)
        sqs_client.delete_queue(QueueUrl=queue_url)
    def test_lambda_put_item_to_dynamodb(self):
        table_name = 'ddb-table-{}'.format(short_uid())