title: Methods to extract email signature
body: <p>I would like to extract email signatures from a single-column Pandas data frame where each row contains a discrete email message as a string. Some emails are HTML encoded and some are not. They can be of any email provider (e.g.: Gmail, Microsoft, Yahoo, etc.).</p>
  
  <p>I know that Gmail signatures are contained in a div where <code>class="email_signature"</code> which simplifies parsing those. My dilemma is: what is the best way to extract non-gmail email signatures? Is there a regex that captures the content of an email? How can I apply this regex over the Pandas data frame in Python?</p>
  
  <p>I'd provide an example but the data is private and frankly I don't think it's necessary for this question.</p>