title: How to access & modify Django template context variables
body: <p>In my urls.py, I map the url accounts/login/ to the login module, with a reference to the template i want to use:</p>
  
  <pre><code>url(r'^accounts/login/$', 'django.contrib.auth.views.login', {'template_name': 'templates/login.html'})
  </code></pre>
  
  <p>This works fine, but I want to change the value of the <code>next</code> property, which specified where the user ought to be redirected after a successful login.  How can I access these variables and print their values, and more importantly, how can I modify them?</p>
  
  <p>Thanks!</p>