title: How to list all existing loggers using python.logging module
body: <p>Is there a way in Python to get a list of all defined loggers?</p>
  <p>I mean, does something exist such as <code>logging.getAllLoggers()</code> which would return a list of <code>Logger</code> objects?</p>
  <p>I searched the python.logging documentation but couldn't find such a method.</p>