title: Get current user in Django admin
body: <p>I have a posting object that can be either accessed in the website or the admin panel. In both, the user is automatically assigned to the post when the user posts it. In the website area, it works fine. However, it does not work in the admin area. First, I tried just having the form input there. When I try to save the object and leave the input blank, it tells me the form has no value. Then, trying to see if I just put in a random value and see if it was overwritten, I did that. However, that random value was not overwritten with the current user. If I excluded the field, when I try to save the model I get an Integrity error saying the field author 'may not be NULL', so I'm assuming my save_model() function is not firing right at all. Now the code I'm using for this I've seen all over the internet and people claim for it to work, I don't know if it's just broken now or what. Here's my code:</p>
  
  <pre><code>from django.contrib import admin
  from posting.models import Posting, Categories
  
  class PostingAdmin(admin.ModelAdmin):
      list_display = ("title","author", "article","date")
      exclude = ('author',)
      fieldsets = (
          (None, {
              'fields': ('title',)
          }),
          ('Body', {
              'fields': ('article',)
              }),
      )
  
      def save_model(self,request,form,obj,change):
          print 'ENTERING SAVE_MODEL FUNCTION'
          if not change:
              obj.author = request.user
              print 'OBJ.AUTHOR:' + str(obj.author)
          obj.save()
          print "EXITING SAVE_MODEL FUNCTION"
  admin.site.register(Posting, PostingAdmin)
  </code></pre>