title: Python Regex: Match paragraph numbers
body: <p>I am attempting to match paragraph numbers inside my block of text. Given the following sentence:</p>
  
  <blockquote>
    <p>Refer to paragraph C.2.1a.5 for examples.</p>
  </blockquote>
  
  <p>I would like to match the word <code>C.2.1a.5</code>.</p>
  
  <p>My current code like so:</p>
  
  <pre><code>([0-9a-zA-Z]{1,2}\.)
  </code></pre>
  
  <p>Only matches <code>C.2.1a.</code> and <code>es.</code>, which is not what I want. Is there a way to match the full <code>C.2.1a.5</code> and not match <code>es.</code>?</p>
  
  <p><a href="https://regex101.com/r/cO8lqs/13723" rel="nofollow noreferrer">https://regex101.com/r/cO8lqs/13723</a></p>
  
  <p>I have attempted to use <code>^</code> and <code>$</code>, but doing so returns no matches.</p>