title: Django auto-populate on admin load
body: <p>I am building a simple Django project to manage a bunch of phone numbers and call logs that we have in Twilio and other cloud telephony providers. I would like to keep in Django a list of the phone numbers that we have in Twilio. I am easily able to query Twilio's API to get our current numbers, and it seems quite simple to use this list to populate my Django DB. </p>
  
  <p>However, to make sure the list in Django is kept in sync with Twilio, I would like to call Twilio's API and update the list of numbers in Django every time a user loads the list of phone numbers in the admin. </p>
  
  <p>Question: how do I get Django to run this call every time the list of numbers loads in the admin?</p>