title: How to reset page number in Django ListView
body: <p>How to reset page number in Django ListView.</p>
  
  <p>There is a view with filter form, results are paginated.</p>
  
  <p>For example:
  First request returns 50 pages, we come to 40 page. Then we change filter, and result is just 10 pages. In the url we have page number 40. And we get 404 page, because result just 10 pages.</p>
  
  <p>Seems I must redirect to the first page while 'POST'. How to make it in ListView</p>