public function scopeIncludes(object $query, ?string $lang = null): Builder 	{ 		return $query->with([ 			'item' => function (MorphTo $morphTo) use ($lang) { 				$morphTo->constrain([ 					Product::class => function (Builder $query) use ($lang) { 						$query->includes($lang)->available(); 					}, 					ProductVariant::class => function (Builder $query) use ($lang) { 						$query->includes($lang)->available(); 					},  				]); 			}, 		]); 	}