title: Django select existing related record, or create new inline
body: <p>I have a django model 'User' with a foreignkey to a related model 'Group'.</p>
  
  <p>I am using a modelForm to render the form for creating a user, which allows the user to select a group from a dropdown of existing groups.</p>
  
  <p>However, I'd like the option for the user to create a 'new' Group within that form if they don't find one they want in the list.</p>
  
  <p>I know I could do an inline form, but I'm not sure how to accomplish that while retaining the ability to optionally select an existing related record.</p>
  
  <p>Any advice?</p>