title: Why does my logging not work in Python 3?
body: <p>I am trying to add a logging handler in Python 3 this way:</p>
  
  <pre><code>$ python3
  Python 3.5.2 (default, Sep 14 2017, 22:51:06) 
  [GCC 5.4.0 20160609] on linux
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt; import logging
  &gt;&gt;&gt; 
  &gt;&gt;&gt; logger = logging.getLogger()
  &gt;&gt;&gt; handler = logging.StreamHandler()
  &gt;&gt;&gt; handler.setLevel(logging.INFO)
  &gt;&gt;&gt; logger.addHandler(handler)
  &gt;&gt;&gt; 
  &gt;&gt;&gt; logging.info("my info")
  &gt;&gt;&gt; logging.warning("my warning")
  my warning
  </code></pre>
  
  <p>I specified loglevel as <code>INFO</code>. Why does <code>logging.info("my info")</code> output nothing?</p>