title: Django admin upload and image to s3 and then resize the image and save a thumb problem
body: <p>I am having error after error trying to upload and resize images to s3 with pil and botos3 and the django default_storage. I am trying to do this on save in the admin.</p>
  
  <p>here is the code:</p>
  
  <pre><code>from django.db import models
  from django.forms import CheckboxSelectMultiple
  
  import tempfile
  
  from django.conf import settings
  
  from django.core.files.base import ContentFile
  from django.core.files.storage import default_storage as s3_storage
  from django.core.cache import cache
  
  from datetime import datetime
  
  import Image, os
  import PIL.Image as PIL
  import re, os, sys, urlparse
  
  class screenshot(models.Model):
      title = models.CharField(max_length=200)
      slug = models.SlugField(max_length=200)
  
      image = models.ImageField(upload_to='screenshots')
      thumbnail = models.ImageField(upload_to='screenshots-thumbs', blank=True, null=True, editable=False)
  
      def save(self):
          super(screenshot, self).save() # Call the "real" save() method
          if self.image:
  
              thumb = Image.open(self.image.path)
              thumb.thumbnail(100, 100)
  
              filename = str(self.slug)
  
              temp_image = open(os.path.join('tmp',filename), 'w')
              thumb.save(temp_image, 'JPEG')
  
              from django.core.files import File
              thumb_data = open(os.path.join('/tmp',filename), 'r')
              thumb_file = File(thumb_data)
  
              new_file.thumb.save(str(self.slug) + '.jpg', thumb_file)
  
  
      def __str__(self):
          return self.title
  </code></pre>
  
  <p>This is just one of the many ways I have tried to get it working, and I either get (2, 'No such file or directory') or some other error.</p>
  
  <p>Please can someone help me to get it working. I want it to use the django backend to get the image uploaded to be resized and saved as the thumbnail and then saved. Let me know if you need to know any information. I would be happy to use the django snippet -  <a href="http://djangosnippets.org/snippets/224/" rel="nofollow">http://djangosnippets.org/snippets/224/</a> but I don't know what data to feed it. I get the same IOErrors and 'no such path/filename' even though the main image is uploading to s3 fine. I have also tried things like:</p>
  
  <pre><code>myimage = open(settings.MEDIA_URL + str(self.image)) 
  myimage_io = StringIO.StringIO()
  imageresize = myimage.resize((100,100), Image.ANTIALIAS)
  imageresize.save('resize_100_100_aa.jpg', 'JPEG', quality=75)
  </code></pre>
  
  <p>It's been 3 days of looking now so I am starting to go spare! Thanks</p>