title: mpi4py and subprocess.Popen()
body: <p>I am trying to write a python script using mpi4py that runs a bunch of executable files using subprocess.Popen() and then post processes them after, therefore I would need to know when the executable files have run.</p>
  
  <p>I am noticing that mpi4py does not like subprocess.Popen() when I run it on a computer cluster. I tried using mpi4py's Spawn() but it does not tell me when the executable file has finished running.</p>
  
  <p>Any ideas on how I should run the executable files. I will be running thousands of these files on multiple nodes.</p>