title: django: Save image from url inside another model
body: <pre><code>class Item(models.Model):
      name = models.CharField(max_length = 200)
      image = models.ImageField(upload_to = 'read', blank=True)
      creative_url = models.CharField(max_length = 200)
      description = RichTextField()
  
      def save(self, *args, **kwargs):
          content = urllib2.urlopen(self.creative_url).read()
          self.image.save("test.jpg", File(content))
          super(Item, self).save(*args, **kwargs)
  </code></pre>
  
  <p>Gives exception:
  'str' object has no attribute 'name'</p>
  
  <p>I was trying to follow this answer (http://stackoverflow.com/questions/1393202/django-add-image-in-an-imagefield-from-image-url) But it did not help to get rid of the exception.</p>
  
  <hr>
  
  <pre><code>AttributeError at /admin/collection/item/1/ 'str' object has no attribute 'name' Request Method:    POST Request
  URL:    http://127.0.0.1:8000/admin/collection/item/1/ Django
  Version:    1.2.5 Exception Type:   AttributeError Exception Value:  'str'
  object has no attribute 'name' Exception
  Location:   D:\FF\django\core\files\base.py in _get_size, line 39 Python
  Executable: C:\Python27\python.exe Python Version:  2.7.2 Python
  Path:   ['D:\\FF',
  'C:\\Python27\\lib\\site-packages\\django_social_auth-0.6.7-py2.7.egg',
  'C:\\Python27\\lib\\site-packages\\python_openid-2.2.5-py2.7.egg',
  'C:\\Python27\\lib\\site-packages\\oauth2-1.5.211-py2.7.egg',
  'C:\\Python27\\lib\\site-packages\\httplib2-0.7.4-py2.7.egg',
  'C:\\Python27\\lib\\site-packages\\selenium-2.20.0-py2.7.egg',
  'C:\\Python27\\lib\\site-packages\\ipython-0.12-py2.7.egg',
  'C:\\Python27\\lib\\site-packages\\django_localeurl-1.5-py2.7.egg',
  'C:\\Python27\\lib\\site-packages\\pil-1.1.7-py2.7-win32.egg',
  'C:\\Python27\\lib\\site-packages\\pip-1.1-py2.7.egg',
  'C:\\Windows\\system32\\python27.zip', 'C:\\Python27\\DLLs',
  'C:\\Python27\\lib', 'C:\\Python27\\lib\\plat-win',
  'C:\\Python27\\lib\\lib-tk', 'C:\\Python27',
  'C:\\Python27\\lib\\site-packages',
  'c:\\python27\\lib\\site-packages'] Server time:    Tue, 24 Apr 2012
  14:19:00 +0300
  </code></pre>