Dinamic upload File type for Gallery

admin.py

from django.contrib import admin
from . import models

class GalleryAdmin(admin.ModelAdmin):
    list_display = ("file_type", "title", "get_absolute_url", "created")
    search_fields= ['title']
    list_filter = ['created']
    list_per_page = 5

admin.site.register(models.Gallery, GalleryAdmin)

models.py

"""
>>> from blog.models import Gallery
>>> 
>>> Gallery.objects.all()[0].file_type()
'<img height="40" width="60" src="gallery/2016/03/17/dhclient.png"/>'
>>> 
>>> Gallery.objects.all()[0].field_uploaded.url
'gallery/2016/03/17/dhclient.png'
>>> 
>>> Gallery.objects.all()[0].get_absolute_url()
'<a href="http://127.0.0.1:8000/gallery/2016/03/17/dhclient.png" target="_blank">http://127.0.0.1:8000/gallery/2016/03/17/dhclient.png</a>'
>>> 
>>>
"""

from django.db import models

class Gallery(models.Model):
    title = models.CharField(max_length=200, help_text="Type title of file or image")
    created = models.DateTimeField(auto_now_add=True)
    modified = models.DateTimeField(auto_now=True)
    
    TIPE = (
                ('image','Image'),
                ('file','File or Documents')
            )

    type_for_file = models.CharField(max_length=200, choices=TIPE, default='image', help_text="Please Choice only One Field, Image or Files")
    field_uploaded = models.FileField(upload_to='gallery/%Y/%m/%d/')

    IMAGES = ['.jpg', '.png', '.jpeg', '.gif']

    def file_type(self):
        if self.type_for_file == 'image':
            import os
            fx = str(os.path.splitext(str(self.field_uploaded.url))[1])
            if fx in self.IMAGES:
                return ('<img height="40" width="60" src="%s"/>' % self.field_uploaded.url)
        elif self.type_for_file == 'file':
            return '<img height="40" width="45" src="/static/asset/icons/file-icon.png"/>'
    file_type.short_description = 'Type'
    file_type.allow_tags = True

    domain = 'http://127.0.0.1:8000/'

    def get_absolute_url(self):
        return '<a href="'+self.domain+self.field_uploaded.url+'" target="_blank">'+self.domain+self.field_uploaded.url+'</a>'
    get_absolute_url.short_description = 'Absolute Url'
    get_absolute_url.allow_tags = True

    def save(self, *args, **kwargs):
        super(Gallery, self).save(*args, **kwargs)
        if not self.file_type():
            raise Exception('Could not uploaded- is the file type valid?')

    def __unicode__(self):
        return self.title

    class Meta:
        verbose_name = "Gallery Entry"
        verbose_name_plural = "Gallery and Files"
        ordering = ["-created"]