title: Python: confusions with urljoin
body: <p>I am trying to form URLs from different pieces, and having trouble understanding the behavior of this method. For example:</p>
  
  <p><strong>Python 3.x</strong></p>
  
  <pre><code>from urllib.parse import urljoin
  
  &gt;&gt;&gt; urljoin('some', 'thing')
  'thing'
  &gt;&gt;&gt; urljoin('http://some', 'thing')
  'http://some/thing'
  &gt;&gt;&gt; urljoin('http://some/more', 'thing')
  'http://some/thing'
  &gt;&gt;&gt; urljoin('http://some/more/', 'thing') # just a tad / after 'more'
  'http://some/more/thing'
  urljoin('http://some/more/', '/thing')
  'http://some/thing'
  </code></pre>
  
  <p>Can you explain the exact behavior of this method?</p>