title: How do I include the id field in a django form?
body: <p>I'm trying to create a simple form that pulls up a record by asking its ID in the form. </p>
  
  <p>views.py</p>
  
  <pre><code>class Bill(models.Model):
      """
      Represents a single purchase made by a customer at a business.
      """
      business = models.ForeignKey(Businesses)
      customer = models.ForeignKey(User, blank=True, null=True)
      charge = models.ForeignKey(Charge, blank=True, null=True)
      amount = models.IntegerField(verbose_name='Purchase amount (in cents)',
                                   validators=[MinValueValidator(0)])
      tip = models.IntegerField(verbose_name='Tip amount (in cents)',
                                   validators=[MinValueValidator(0)])
      comments = models.CharField(max_length=255, blank=True, null=True)
      timestamp = models.DateTimeField(auto_now_add=True)
  </code></pre>
  
  <p>forms.py</p>
  
  <p>from django import forms
      from django.forms import ModelForm
      from transactions.models import Bill</p>
  
  <pre><code>class BillSelectForm(ModelForm):
      class Meta:
          model = Bill
          fields = ('id',)
  </code></pre>
  
  <p>views.py </p>
  
  <pre><code>@login_required(login_url='/sign-in/')
  def select_bill(request):
      """
      Finds a bill based on its ID number.
      """
      if request.method == 'POST':
          form = BillSelectForm(request.POST)
          if form.is_valid():
              pass
              # look up db for id number
              # go to bill view page if id found AND bill not paid
              # go back to same page and create message saying wrong bill
  
      else:
          form = BillSelectForm()
  
      return render(request, 'bill_select.html', {'form': form})
  </code></pre>
  
  <p>However, on the template, when I use <code>{{ form.as_p }}</code>, I'm seeing nothing at all. Thoughts?</p>