title: Extract email sub-strings from large document
body: <p>I have a very large .txt file with hundreds of thousands of email addresses scattered throughout.  They all take the format:</p>
  
  <pre><code>...&lt;name@domain.com&gt;...
  </code></pre>
  
  <p>What is the best way to have Python to cycle through the entire .txt file looking for a all instances of a certain @domain string, and then grab the entirety of the address within the &lt;...>'s, and add it to a list?  The trouble I have is with the variable length of different addresses.</p>