title: Pycharm unit test interactive debug command line doesn't work
body: <p>When debugging unit tests (through the pycharm test runner), one can turn on the interactive command line, but (unlike when debugging regular scripts) the commands entered don't produce any output. As a matter of fact, it appears that stdout is being captured somewhere, because stderr works as expected:</p>
  
  <pre><code>&gt;&gt;&gt; print "a"
  &gt;&gt;&gt; import sys
  &gt;&gt;&gt; sys.stderr.write("moof")
  moof
  &gt;&gt;&gt; sys.stdout.write("moof")
  &gt;&gt;&gt; sys.stderr.write("test")
  test
  </code></pre>
  
  <p>Is this expected behavior? I really like the interactive debug console and it would be awesome if it behaved nice when debugging unit tests as well.</p>