title: python regex of a date in some text
body: <p>How can I find as many date patterns as possible from a text file by python? The date pattern is defined as:</p>
  
  <pre><code>dd mmm yyyy
    ^   ^
    |   |
    +---+--- spaces
  </code></pre>
  
  <p>where:</p>
  
  <ul>
  <li><strong>dd</strong> is a two digit number</li>
  <li><strong>mmm</strong> is three-character English month name (e.g. Jan, Mar, Dec)</li>
  <li><strong>yyyy</strong> is four digit year</li>
  <li>there are two <strong>spaces</strong> as separators</li>
  </ul>
  
  <p>Thanks!</p>