old_contents: from django.db import models
  from django.urls import reverse
  
  from dotmanca.storage import OverwriteStorage
  
  
  class Gallery(models.Model):
      name = models.CharField(max_length=50)
      slug = models.SlugField(unique=True)
      added_timestamp = models.DateTimeField(auto_now_add=True)
      description = models.TextField(blank=True)
      sort_order = models.IntegerField()
  
      def get_absolute_url(self):
          kwargs = {'slug': self.slug}
          return reverse('gallery:gallery', kwargs=kwargs)
  
      def __str__(self):
          return self.name
  
      class Meta:
          verbose_name_plural = 'galleries'
  
  
  def gallery_image_upload_to(instance, file_name):
      file_extension = file_name.split(".")[-1]
      return F'galleries/{instance.gallery.slug}/{instance.slug}.{file_extension}'
  
  
  class GalleryImage(models.Model):
      gallery = models.ForeignKey(Gallery, on_delete=models.CASCADE)
      name = models.CharField(max_length=50)
      slug = models.SlugField()
      sort_order = models.IntegerField()
  
      the_image = models.ImageField(null=False, blank=False, upload_to=gallery_image_upload_to,
                                    storage=OverwriteStorage())
      added_timestamp = models.DateTimeField(auto_now_add=True)
      description = models.TextField(blank=True)
  
      def get_absolute_url(self):
          kwargs = {'gallery_slug': self.gallery.slug, 'slug': self.slug}
          return reverse('gallery:gallery_image', kwargs=kwargs)
  
      def __str__(self):
          return self.name
  
      class Meta:
          unique_together = ('gallery', 'slug')
  
new_contents: from django.db import models
  from django.urls import reverse
  
  from dotmanca.storage import OverwriteStorage
  
  
  class Gallery(models.Model):
      name = models.CharField(max_length=50)
      slug = models.SlugField(unique=True)
      added_timestamp = models.DateTimeField(auto_now_add=True)
      description = models.TextField(blank=True)
      sort_order = models.IntegerField()
  
      def get_absolute_url(self):
          kwargs = {"slug": self.slug}
          return reverse("gallery:gallery", kwargs=kwargs)
  
      def __str__(self):
          return self.name
  
      class Meta:
          verbose_name_plural = "galleries"
  
  
  def gallery_image_upload_to(instance, file_name):
      file_extension = file_name.split(".")[-1]
      return f"galleries/{instance.gallery.slug}/{instance.slug}.{file_extension}"
  
  
  class GalleryImage(models.Model):
      gallery = models.ForeignKey(Gallery, on_delete=models.CASCADE)
      name = models.CharField(max_length=50)
      slug = models.SlugField()
      sort_order = models.IntegerField()
  
      the_image = models.ImageField(
          null=False,
          blank=False,
          upload_to=gallery_image_upload_to,
          storage=OverwriteStorage(),
      )
      added_timestamp = models.DateTimeField(auto_now_add=True)
      description = models.TextField(blank=True)
  
      def get_absolute_url(self):
          kwargs = {"gallery_slug": self.gallery.slug, "slug": self.slug}
          return reverse("gallery:gallery_image", kwargs=kwargs)
  
      def __str__(self):
          return self.name
  
      class Meta:
          unique_together = ("gallery", "slug")
  
subject: Format using formatting tool