title: How to use for/in with tuples?
body: <p>Is it possible to do something like:</p>
  
  <pre><code>for (a,b) in (1,2) (2,1)
  do
  run_program.py $a $b
  done
  </code></pre>
  
  <p>I only know the <code>for do done</code> syntax in Linux. I want to run the program with the specific two (a,b) instances (or course, it easily generalizes to much larger than two).</p>