title: Which whois servers does this library use and are they rate limited?
body: <p>I can't seem to locate which whois servers this library uses, where in the code does it have the URL of the server(s) it connects too?</p>
  
  <p>I'm not sure I understand how whois actually works, but I am assuming it connects to popular registrars API's correct?</p>
  
  <p>Does this mean that if I try and run a whois for thousands of entries I will be rate limited and the response will begin to fail?</p>