How to make python wait for a program to stop before going to the next line of code

I'm creating a script in python that will open a program then python will wait for that program to close itself before continuing to the next code. Here is my script:

Import subprocess as sp
sp.Popen([r'C:/Folder/folder/a.exe'])
??????
????????
print("test")

The question marks are the things that I don't know.

2 Answers

Try subprocess.call instead of Popen. It waits for the command to complete.

import subprocess
subprocess.call('a.exe')
print("test")

For reference.

@Legate77's answer is correct, but for versions > 3.5, subprocess.run is preferred:

import subprocess
subprocess.run(['./a.out', 'arg1', 'arg2'])
print('done')

Documentation is on the same page