title: How to execute ipdb.set_trace() at will while running pytest tests
body: <p>I'm using pytest for my test suite. While catching bugs in complex inter-components test, I would like to place <code>import ipdb; ipdb.set_trace()</code> in the middle of my code to allow me to debug it.</p>
  
  <p>However, since pytest traps sys.stdin/sys.stdout ipdb fails. How can I use ipdb while testing with pytest.</p>
  
  <p>I'm not interested in jumping to pdb or ipdb after a failure, but to place breaks anywhere in the code and be able to debug it there before the failure occurs.</p>