title: Prepopulating a form Select field in django with specific values and initializing it
body: <p>I have a model in django that has a foreign key to the django user model</p>
  
  <pre><code>class Entry(models.Model):
      user = models.ForeignKey(User)
  </code></pre>
  
  <p>and a corresponding model form</p>
  
  <pre><code>class EntryForm(ModelForm)
  
      class Meta:
          model = Entry
  </code></pre>
  
  <p>The user field uses a Select widget. I want this widget to only have staff users. So I tried the following. </p>
  
  <p>Ιn the view:</p>
  
  <pre><code>form = EntryForm(initial={'user':User.objects.filter(is_staff=True)}
  </code></pre>
  
  <p>but didn't work. The Select widget shows all users staff and non-staff</p>
  
  <p>Then i tried this:
      form = EntryForm()
      form.fields['user'].queryset = User.objects.filter(is_staff = True)</p>
  
  <p>and worked. 
  What i want to do is narrow the options of the select user to staff only users but I want to be able to have pre-selected a certain value, e.g the user logged in(staff user).e.g </p>
  
  <pre><code>form = EntryForm(initial={'user':request.user}) #pre-select specific user
  form.fields['user'].queryset = User.objects.filter(is_staff = True) #only show staff users
  </code></pre>
  
  <p>but this doesn't work. Let me say here that i want to initialize other form fields too e.g date and other, but i have left them out for simplicity.</p>
  
  <p>I also tried using the <strong>init</strong> method of form, but won't work well with the above code</p>
  
  <pre><code>def __init__(self, *args, **kwargs):
      pass
  </code></pre>
  
  <p>gives me an error(used pass for testing purposes). </p>
  
  <pre><code>AttributeError
      'EntryAddForm' object has no attribute 'fields'
  </code></pre>
  
  <p>So is there a way to do initialize a Select field in a form and also exclude or include a certain queryset at the same time in that field?</p>