code: func NewOperationExecutor(
  	operationGenerator OperationGenerator) OperationExecutor {
  
  	return &operationExecutor{
  		pendingOperations: nestedpendingoperations.NewNestedPendingOperations(
  			true /* exponentialBackOffOnError */),
  		operationGenerator: operationGenerator,
  	}
  }
docs: // NewOperationExecutor returns a new instance of OperationExecutor.