title: Send commands serially with delay between commands
body: <p>I've got the list of commands, it just takes them from a treeview. The treeview has three columns (line number, cmd, and delay). </p>
  
  <p>I know how to send the commands serially,  but I dont know how to implement the delay wanted, then send the next command. But it also needs to be able to pause and stop whenever a button is pushed. So first line is (1,50, 2). </p>
  
  <p>When the start button is pushed, it would send the cmd "50" then wait 2 seconds before going to the next line. If I hit pause, then resume it needs to pick up where it left off, or hitting stop to stop it completely. I am writing in python. Any ideas on how to achieve this? </p>
  
  <p>The question is how to put this in a queue of some sorts,  go through the queue reading each line,  sending the command,  waiting the time specified, then going to the next item in the queue. </p>
  
  <p><strong>Note</strong> : I need to be able to pause and/or stop this with a push of a button. </p>