title: replace pattern in text file
body: <p>Below my sample html file:</p>
  
  <pre><code>some text here &lt;img src="http://site.com/7b399e20/77165/5fa/2a31ffb8.jpg"/&gt; sometext here
  
  some text here &lt;img src="http://site.com/7b399e20/2a31ffb8.jpg"/&gt; sometext here
  
  some text here &lt;img src="http://site.com/7b399e20/2a31ffb8.png"/&gt; sometext here
  
  some text here &lt;img src="http://site.com/2a31ffb8.jpeg"/&gt; sometext here
  </code></pre>
  
  <p>how do I make such a transformation:</p>
  
  <pre><code>some text here &lt;img src="web/2a31ffb8.jpg"/&gt; sometext here
  
  some text here &lt;img src="web/2a31ffb8.jpg"/&gt; sometext here
  
  some text here &lt;img src="web/2a31ffb8.png"/&gt; sometext here
  
  some text here &lt;img src="web/2a31ffb8.jpeg"/&gt; sometext here
  </code></pre>
  
  <p>Thanks</p>