title: How to find overlapping matches with a regexp?
body: <pre><code>&gt;&gt;&gt; match = re.findall(r'\w\w', 'hello')
  &gt;&gt;&gt; print match
  ['he', 'll']
  </code></pre>
  
  <p>Since \w\w means two characters, 'he' and 'll' are expected. But why do 'el' and 'lo' <strong>not</strong> match the regex?</p>
  
  <pre><code>&gt;&gt;&gt; match1 = re.findall(r'el', 'hello')
  &gt;&gt;&gt; print match1
  ['el']
  &gt;&gt;&gt;
  </code></pre>