public function calculateShipping(): self 	{ 		$this->order->total_weight = $this->order->getProducts()->sum('weight'); 		$shipping_provider = ShippingProvider::from($this->request->input('shipping_provider')); 		$this->order->shipping_provider = $shipping_provider; 		$this->order->setShippingCost($this->shippingCalculationService->calculate($this->order->total_weight, strtolower($shipping_provider->name), $this->order->final_price));  		return $this; 	}