issue in ImageThumbnailFileInput in django forms

i am using django-floppyforms in my project
but it can't get preview image in template
i folow example from
http://django-floppyforms.readthedocs.org/en/latest/examples.html#an-image-clearable-input-with-thumbnail

my forms.py

``` python
from django import forms
import datetime
from .models import Product
from hvad.forms import TranslatableModelForm
from ajax_upload.widgets import AjaxClearableFileInput
from django.utils.translation import ugettext_lazy as _
from crispy_forms.helper import FormHelper
from crispy_forms import layout, bootstrap
from crispy_forms.helper import FormHelper
#from crispy_forms.layout import Layout, Fieldset, ButtonHolder, Submit, HTML

from floppyforms import ClearableFileInput
import floppyforms as forms

class ImageThumbnailFileInput(forms.ClearableFileInput):
template_name = 'floppyforms/image_thumbnail.html'

class ProductForm(TranslatableModelForm):
class Meta:
model = Product
fields = ('product_name','category','pro_image1','pro_image2','pro_image3','pro_image4','price','negotiable','des','dis_code')
widgets = {'pro_image1': ImageThumbnailFileInput,
'pro_image2': ImageThumbnailFileInput,
'pro_image3': ImageThumbnailFileInput,
'pro_image4': ImageThumbnailFileInput,
}
```

my "models.py "

``` python
pro_image1 = models.FileField(upload_to='products/',blank=True, null=True, verbose_name = _('Product Image1')),
pro_image2 = models.FileField(upload_to='products/',blank=True, null=True, verbose_name = _('Product Image2')),
pro_image3 = models.FileField(upload_to='products/',blank=True, null=True, verbose_name = _('Product Image3')),
pro_image4 = models.FileField(upload_to='products/',blank=True, null=True, verbose_name = _('Product Image4')),

```

image_thumbnail.html

```
{# image_thumbnail.html #}
{% load i18n %}
{% if value.url %}{% trans "Currently:" %}
{% if not required %}

{% trans "Clear" %}

{% else %}

{% endif %}
{% trans "Change:" %}
{% endif %}

```

i also try with imagefields in models.py
how can i solve this ,
Pls help!!!

Start by reproducing the form rendering described in forms.py with the model fields in models.py, then compare the result with the linked floppyforms thumbnail example. Inspect image_thumbnail.html and verify whether the submitted image value exposes the expected URL; done means an existing image preview renders in the template.

Written by the indexing model from the issue text.