initions"><li><tt>El = <a href="exmpp_xml.html#type-xmlel">exmpp_xml:xmlel()</a></tt></li><li><tt>Type = Challenge | Success | Failure</tt></li><li><tt>Challenge = {challenge, string()}</tt></li><li><tt>Success = {success, string()}</tt></li><li><tt>Failure = {failure, Condition | undefined}</tt></li><li><tt>Condition = atom()</tt></li></ul></p>
</div><p><p>Extract the challenge or the ending element that the receiving  
entity sent.</p>
 
  Any challenge or success data is Base64-decoded.</p>

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