title: Checking if a user has been assigned a token in Django Restframework
body: <p>I am setting up token authentication for a site using Django Restframework and need to be able to have a user download their token, however the catch is that they much only be able to download their token once (similar to the Amazon AWS model). </p>
  
  <p>In other words; is there a native way to check if a user has been assigned a token in restframework?  </p>