title: Big text files in python
body: <p>I have to write some Python code to read a file in the following format:</p>
  
  <pre><code>&lt;doc&gt; 
  Hello Word
  &lt;/doc&gt;
  &lt;doc&gt;
  Hello blah blah
  &lt;/doc&gt;
  </code></pre>
  
  <p>Then I have to count how many of those tags contains a determined word.</p>
  
  <p>For example, if I'm searching for the word blah it should return 1, and if I'm searching for the word Hello, it should return 2.</p>
  
  <p>Also, is there a way to do it efficiently? The files are pretty big (approximately 250mb of text).</p>