title: Python - Extract text that starts with a particular sub-string
body: <p>I am working on extracting certain text from emails using Python Regex</p>
  <p>I have tried below:</p>
  <pre><code>import re
  
  email = &quot;&quot;&quot;Hi John,
  
  I am emailing regarding REQ-12345 and REQ-66442.
  
  Many Thanks,
  
  Jane&quot;&quot;&quot;
  
  
  re.findall(r'(?=REQ-)',email)
  </code></pre>
  <p>Expected Output: <code>['REQ-12345', 'REQ-66442']</code></p>
  <p>Actual Output: <code>['', '']</code></p>
  <p>I have also tried multiple different things which aren't giving the right results.</p>
  <p>How do I achieve the desired output?</p>