title: Change django admin's foreign key widget
body: <p>I have a few models in my django project: CoursePacks, Courses and Chapters.</p>
  
  <p>Courses have a many-to-many relationship to the CoursePacks, which in the admin, after some inline editing, displays this widget:</p>
  
  <p>(This is a COURSE-COURSEPACK relationship)</p>
  
  <p><a href="https://i.stack.imgur.com/ykGBp.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ykGBp.png" alt="COURSE PACK ADMIN COURSES RELATIONSHIP "></a></p>
  
  <p>Which allows me to select, edit and create another course which will be automatically added to the course pack.</p>
  
  <p>The chapter ("capítulo") and the course models, however, are connected through a foreign key relationship, and the widget displayed on the admin is the following:</p>
  
  <p>(This is A CHAPTER-COURSE relationship) </p>
  
  <p><a href="https://i.stack.imgur.com/KPhOA.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/KPhOA.png" alt="COURSE ADMIN CHAPTERS RELATIONSHIP"></a></p>
  
  <p>Which I have edited so that less fields are shown, because if I didn't all the fields and the entire textarea content would be displayed. </p>
  
  <p>When I click on the add or edit button to the side of the course instance on the course pack admin window, a window pops up which allows me to edit or create another course.</p>
  
  <p>I would like to be able to have a similar mechanism but for creating chapters through the course admin window. Will I have to edit the admin's markup or is there a widget editing functionality that does what I need? </p>
  
  <p>If not, where could I begin to do so?</p>