public override void Invoke(AWSCredentials creds, RegionEndpoint region, int maxItems)
        {
            AmazonSimpleWorkflowConfig config = new AmazonSimpleWorkflowConfig();
            config.RegionEndpoint = region;
            ConfigureClient(config);            
            AmazonSimpleWorkflowClient client = new AmazonSimpleWorkflowClient(creds, config);
            
            History resp = new History();
            do
            {
                GetWorkflowExecutionHistoryRequest req = new GetWorkflowExecutionHistoryRequest
                {
                    NextPageToken = resp.NextPageToken
                    ,
                    MaximumPageSize = maxItems
                                        
                };

                resp = client.GetWorkflowExecutionHistory(req);
                CheckError(resp.HttpStatusCode, "200");                
                
                foreach (var obj in resp.Events)
                {
                    AddObject(obj);
                }
                
            }
            while (!string.IsNullOrEmpty(resp.NextPageToken));
        }