Automate the rerun of dynamo model and save the revit files

Hi, this is my second day using pyRevit. I am really exciting to get to know that pyRevit is so powerful!

Actually, now I have a Dynamo model, which requirs several different element selections as the input. The output I want is the revit model after running the dynamo model. Since I used random function in the Dynamo model, each time the output model is different.
Now, I want to run the Dynamo model for 20 times and I don’t want to run it manually but automate the process. Therefore, I can get the 20 revit files automatically.

I checked this video in youtube:

It taught how to run Dynamo in pyRevit, but it cannot automate running the model and saving the resuilt revit files.

May I ask if there any way I can achieve this task?