If set, specifies the default maximum duration for executions of this workflow type. You can override this default when starting an
            execution through the StartWorkflowExecution Action or StartChildWorkflowExecutionDecision. The duration is specified
            in seconds. The valid values are integers greater than or equal to 0. Unlike some of the other timeout parameters in Amazon SWF, you cannot
            specify a value of "NONE" for defaultExecutionStartToCloseTimeout; there is a one-year max limit on the time that a workflow
            execution can run. Exceeding this limit will always cause the workflow execution to time out.
             
            
Constraints:
 Declaration Syntax
 Declaration Syntax| C# | 
public string DefaultExecutionStartToCloseTimeout { get; set; }