title: How do I call a model method in django ModelAdmin fieldsets?
body: <p>I want to display an embedded map on an admin form when data already exists in the db. I have the following code:</p>
  
  <p>models.py</p>
  
  <pre><code>class Address(models.Model):
      address = models.CharField()
  
      def address_2_html(self):
          if self.address:
              # Return html for an embedded map using the entered address.
              return embedded_map_html
          else:
              return ''
      address_2_html.allow_tags = True
  </code></pre>
  
  <p>admin.py</p>
  
  <pre><code>class AddressAdmin(admin.ModelAdmin):
      fieldsets = [(label, {'fields': ['address','address_2_html']}),]
  </code></pre>
  
  <p>This doesn't work.  I get an error:</p>
  
  <pre><code>'AddressAdmin.fieldsets[1][1]['fields']' refers to field 'address_2_html' that is missing from the form.
  </code></pre>
  
  <p>Another thing I tried was using the 'description' option for 'fieldsets', however, 'address_2_html' is not accessible within the scope of AddressAdmin.  I did succeed at embedding a static map using 'description' which was cool but not cool enough.</p>