title: django admin: How to customize one field in fieldsets?
body: <p>I try to make one field in django admin's fieldsets to show only certain data, but according to <a href="https://docs.djangoproject.com/en/dev/ref/contrib/admin/#django.contrib.admin.ModelAdmin.list_display" rel="noreferrer">django document</a>, only an example of <code>list_display</code> is shown to be able to customize. I tried the similar approach on <code>fieldsets</code> like the following:</p>
  
  <p>In models.py:</p>
  
  <pre><code>def ports_with_same_scanner(self):
      return PortList.objects.filter(scanner=self.scanner)
  ports_with_same_scanner.short_description = 'port_lists'
  </code></pre>
  
  <p>In admin.py, this won't work:</p>
  
  <pre><code>fieldsets = (
              ('Scan Template', { 
              'fields': ( ('name', 'scanner', 'ports_with_same_scanner',), 'comment', ('in_use',
                  'fc_growing', 'nc_growing'), 'nvt_prefs')
              }),
  )
  </code></pre>
  
  <p>However, if I do this:</p>
  
  <pre><code>list_display = ('name', 'scanner', 'ports_with_same_scanner', 'comment', 'in_use', 'fc_growing', 'nc_growing', 'nvt_prefs')
  </code></pre>
  
  <p>the <code>ports_with_same_scanner</code> works just fine. The problem is that I don't want to change my display from <code>fieldsets</code> to <code>list_display</code>, I wonder how can I achieve the same functionality. Thanks.</p>