I have some models like that:

```
class BaseModel(models.Model):
    created_by = models.ForeignKey(User, related_name="%(app_label)s_%(class)s_created")
    created_date = models.DateTimeField(_('Added date'), auto_now_add=True)
    last_updated_by = models.ForeignKey(User, related_name="%(app_label)s_%(class)s_updated")
    last_updated_date = models.DateTimeField(_('Last update date'), auto_now=True)

    class Meta:
        abstract = True

class Image(BaseModel):
    content_type = models.ForeignKey(ContentType)
    object_id = models.PositiveIntegerField()
    content_object = generic.GenericForeignKey('content_type', 'object_id')

    name = models.CharField(_('Item name'), max_length=200, blank=True)
    image = models.ImageField(_('Image'), upload_to=get_upload_path)

    def save(self, *args, **kwargs):
        if self.image and not GALLERY_ORIGINAL_IMAGESIZE == 0:
            width, height = GALLERY_ORIGINAL_IMAGESIZE.split('x')
            super(Image, self).save(*args, **kwargs)

            filename = os.path.join( settings.MEDIA_ROOT, self.image.name )
            image = PILImage.open(filename)

            image.thumbnail((int(width), int(height)), PILImage.ANTIALIAS)
            image.save(filename)

        super(Image, self).save(*args, **kwargs)

class Album(BaseModel):
    name = models.CharField(_('Album Name'), max_length=200)
    description = models.TextField(_('Description'), blank=True)
    slug = models.SlugField(_('Slug'), max_length=200, blank=True)
    status = models.SmallIntegerField(_('Status'),choices=ALBUM_STATUSES)

    images = generic.GenericRelation(Image)

```

I use BaseModel abstract model for my all models to track save and update logs. I can use ModelAdmin class to set user fields automatically:

```
class BaseAdmin(admin.ModelAdmin):
    def save_model(self, request, obj, form, change):
        if not change:
            obj.created_by = request.user

        obj.last_updated_by = request.user
        obj.save()

class AlbumAdmin(BaseAdmin):
    prepopulated_fields = {"slug": ("name",)}
    list_display = ('id','name')
    ordering = ('id',)

```

That works. All BaseAdmin fields are filled automatically. But I want to add Images to Albums by Inline. So, I change my admin.py like that:

```
from django.contrib.contenttypes import generic

class ImageInline(generic.GenericTabularInline):
    model = Image
    extra = 1

class AlbumAdmin(BaseAdmin):
    prepopulated_fields = {"slug": ("name",)}
    list_display = ('id','name')
    ordering = ('id',)

    inlines = [ImageInline,]

```

When I save page, I get an error: `gallery_image.created_by_id may not be NULL` on first `super(Image, self).save(*args, **kwargs)` row of Image model save method. I know it's because of GenericTabularInline class doesn't have a "save\_model" method to override.

So, the question is, how can I override save method and set current user on InlineModelAdmin classes?