public function getCategoryByIdOrSlug(string $category, ?string $lang): self 	{ 		$category = Category::includes($lang)->available()->where(function ($query) use ($category) { 			$query->where('id', $category) 				->orWhere('slug', $category) 				->orWhereHas('translations', function ($query) use ($category) { 					$query->where([ 						['column', 'slug'], 						['value', $category], 					]); 				}); 		})->firstOrFail();  		return $category; 	}