<fieldset class="module aligned {{ fieldset.classes }}">
  {% if fieldset.name %}
<h2>{{ fieldset.name }}</h2>
{% endif %}
  {% if fieldset.description %}
<div class="description">{{ fieldset.description|safe }}</div>
{% endif %}
  {% for line in fieldset %}
<div class="form-row{% if line.errors %} errors{% endif %} {% for field in line %}{{ field.field.name }} {% endfor %} ">
      {{ line.errors }}
      {% for field in line %}
          {% if field.is_checkbox %}
              {{ field.field }}{{ field.label_tag }}
          {% else %}
              {{ field.label_tag }}{{ field.field }}
          {% endif %}
          {% if field.field.field.help_text %}
{{ field.field.field.help_text|safe }}
{% endif %}</div>
{% endfor %}
  {% endfor %}
</fieldset>

from django.db import models
from django.contrib import admin
 
# Import our custom widget and our model from where they're defined
from myapp.widgets import RichTextEditorWidget
from myapp.models import MyModel
 
class MyModelAdmin(admin.ModelAdmin):
    formfield_overrides = {
        models.TextField: {'widget': RichTextEditorWidget},
    }

def render(self, name, value, attrs=None):
        output = []
        if value and hasattr(value, "url"):
            output.append('%s <img src="%s" alt="" />
%s ' % \
                (_('Currently:'), value.url,  _('Change:')))
        output.append(super(AdminFileWidget, self).render(name, value, attrs))
        return mark_safe(u''.join(output))

from django.db.models.fields.files import ImageField, ImageFieldFile
 
class CoverImageFieldFile(ImageFieldFile):
    def save(self, name, content, save=True):
        import time, random
        parts = name.split(".")
        new_name = time.strftime('%Y%m%d%H%M%S')
        new_name += '%d' % random.randint(1000,9999)
        new_name += '.%s' % parts[-1]
        super(CoverImageFieldFile, self).save(new_name, content, save)
 
class CoverImageField(ImageField):
 
    attr_class = CoverImageFieldFile
    def __init__(self, *args, **kwargs):
        super(CoverImageField, self).__init__(*args, **kwargs)