title: django imagefield model
body: <p>how can I define it in the model if I want the image to save in the path 'img/'currentdateMonthYear_ + category_+ the given name. The category depend on what I choose?</p>
  
  <p>currently I describe my model as such:</p>
  
  <pre><code>class Image(models.Model):
      title       = models.CharField(max_length=50)
      description     = models.TextField()
      hits        = models.IntegerField()
      timestamp   = models.DateTimeField(auto_now_add=True)
      thumb       = models.ImageField(upload_to='photos...
      tag         = models.ForeignKey(Tag)
      artist      = models.ForeignKey(User)
      storage     = models.ForeignKey(Storage)
      market      = models.ForeignKey(Market)
      Category    = models.ForeignKey(Category)
      Log         = models.ForeignKey(Log)
  
      def __unicode__(self):
          return self.title
  </code></pre>