text: class Category(CategoryBase):
      thumbnail = models.FileField(
          upload_to=THUMBNAIL_UPLOAD_PATH, 
          null=True, blank=True,
          storage=STORAGE(),)
      thumbnail_width = models.IntegerField(blank=True, null=True)
      thumbnail_height = models.IntegerField(blank=True, null=True)
      order = models.IntegerField(default=0)
      alternate_title = models.CharField(
          blank=True,
          default="",
          max_length=100,
          help_text="An alternative title to use on pages with this category.")
      alternate_url = models.CharField(
          blank=True, 
          max_length=200, 
          help_text="An alternative URL to use instead of the one derived from "
                    "the category hierarchy.")
      description = models.TextField(blank=True, null=True)
      meta_keywords = models.CharField(
          blank=True,
          default="",
          max_length=255,
          help_text="Comma-separated keywords for search engines.")
      meta_extra = models.TextField(
          blank=True,
          default="",
          help_text="(Advanced) Any additional HTML to be placed verbatim "
                    "in the &lt;head&gt;")