Hi,
It seems like when you have an SQS Queue invoking an Lambda function, that it does get the SQS message, however it seems that the MessageAttributes is always an empty object, even though there is MessageAttributes sent a long.


'<ResponseMetadata>'  
            '<RequestId>00000000-0000-0000-0000-000000000000</RequestId>'  
        '</ResponseMetadata>'  
    '</SendMessageResponse>'  
)
class ProxyListenerSQS(ProxyListener):
    def forward_request(self, method, path, data, headers):
        if method == 'POST':
            req_data = urlparse.parse_qs(to_str(data))
            if 'QueueName' in req_data:
                encoded_data = urlencode(req_data, doseq=True)
                request = Request(data=encoded_data, headers=headers, method=method)
                return request
            elif req_data.get('Action', [None])[0] == 'SendMessage':
                queue_url = req_data.get('QueueUrl', [path])[0]
                queue_name = queue_url[queue_url.rindex('/') + 1:]
                message_body = req_data.get('MessageBody', [None])[0]
                if lambda_api.process_sqs_message(message_body, queue_name):
                    
                    new_response = Response()
                    new_response._content = SUCCESSFUL_SEND_MESSAGE_XML_TEMPLATE.format(
                        message_attr_hash=md5(data),
                        message_body_hash=md5(message_body),
                        message_id=str(uuid.uuid4()),
                    )
                    new_response.status_code = 200
                    
                    return new_response
        return True
    def return_response(self, method, path, data, headers, response, request_handler):