title: communication between 2 programs in python
body: <p>I have 2 programs that are both in python, one is 3rd Party and already been made. I want to run one in the foreground and one in the background. I want to set up a communication between the 2 programs, so I can tell the one in the foreground to do something, and it then tell the other program to do something. Such as on the foreground program I press a button, which then tell the other program to do something.
  What is the best way to do bout this?</p>
  
  <p>I know I have asked a question about this before, but I feel that people might have found that too specific, so I have written a more simplified question.</p>