title: Is there a master list somewhere of the tags and their meanings for mhtml files?
body: <p>I am trying to read and extract data from xls files that are really Single File Web Pages see below</p>
  
  <pre><code>This document is a Single File Web Page, also known as a Web Archive file.  
  </code></pre>
  
  <p>I am trying to figure out the meaning of all of the tags so I can make sure I parse them correctly using lxml.</p>
  
  <p>For example here is an example of a tag:  </p>
  
  <pre><code> &lt;th class=3Dtl colspan=3D1 rowspan=3D2
  </code></pre>
  
  <p>While I am having success working with the few files I am toying with I want to try to figure out if I am making assumptions that will later come back to haunt me.  Thus, a list of these tags and their meaning would be great.</p>