Как я могу разделить заказы по атрибутам в моем API

У меня есть метод, который создает заказ из корзины пользователя. Чтобы курьер забирал заказ из разных ресторанов, заказ делится на несколько. Но в данный момент я разделяю заказ только по блюду в корзине. Как сделать чтобы заказ разделялся по ресторанам, то есть если пользователь заказывает 5 блюд из двух разных ресторанов, то формировалось 2 заказа

views.py

@action(methods=['PUT'], detail=False, url_path='current_customer_cart/add_to_order')
    def add_cart_to_order(self, *args, **kwargs):
        cart = Cart.objects.get(owner=self.request.user.customer)
        cart_meals = CartMeal.objects.filter(cart=cart)
        data = self.request.data

        for cart_meal in cart_meals:
            order = Order.objects.create(customer=self.request.user.customer,
                                         cart_meal=cart_meal,
                                         first_name=data['first_name'],
                                         last_name=data['last_name'],
                                         phone=data['phone'],
                                         address=data.get('address', self.request.user.customer.home_address),
                                         restaurant_address=cart_meal.meal.restaurant.address,
                                         )
            order.save()
        return response.Response({"detail": "Order is created", "added": True})

models.py

class Order(models.Model):
    """User's order"""

    customer = models.ForeignKey(Customer, on_delete=models.CASCADE, related_name='related_orders')
    first_name = models.CharField(max_length=255)
    last_name = models.CharField(max_length=255)
    phone = models.CharField(max_length=20)
    cart_meal = models.ForeignKey(CartMeal, on_delete=models.CASCADE, null=True, blank=True)
    restaurant_address = models.CharField(max_length=1024, null=True)
    address = models.CharField(max_length=1024)
    status = models.CharField(max_length=100, choices=STATUS_CHOICES, default=STATUS_NEW)
    created_at = models.DateTimeField(auto_now=True)
    delivered_at = models.DateTimeField(null=True, blank=True)
    courier = models.OneToOneField('Courier', on_delete=models.SET_NULL, null=True, blank=True)

class CartMeal(models.Model):
    """Cart Meal"""

    user = models.ForeignKey('Customer', on_delete=models.CASCADE)
    cart = models.ForeignKey('Cart', verbose_name='Cart', on_delete=models.CASCADE, related_name='related_meals')
    meal = models.ForeignKey(Meal, verbose_name='Meal', on_delete=models.CASCADE)
    qty = models.IntegerField(default=1)
    final_price = models.DecimalField(max_digits=9, decimal_places=2)

class Meal(models.Model):
    """Meal"""

    title = models.CharField(max_length=255)
    description = models.TextField(default='The description will be later')
    price = models.DecimalField(max_digits=9, decimal_places=2)
    discount = models.IntegerField(default=0)
    restaurant = models.ForeignKey(Restaurant, on_delete=models.CASCADE, null=True)
    slug = models.SlugField(unique=True)

class Restaurant(models.Model):
    """Restaurant"""

    name = models.CharField(max_length=255)
    slug = models.SlugField(unique=True)
    address = models.CharField(max_length=1024)
    owner = models.ForeignKey('Restaurateur', on_delete=models.CASCADE, null=True)
    meals = models.ManyToManyField('Meal', related_name='related_restaurant', blank=True)

Как я могу это сделать, пожалуйста, помогите мне

import itertools
from core.models import CartMeal, Order


for restaurant, cart_meals in itertools.groupby(CartMeal.objects.order_by('meal__restaurant'), lambda s: s.meal.restaurant):
    order = Order.objects.create(
        customer=self.request.user.customer,
        first_name=data['first_name'],
        last_name=data['last_name'],
        phone=data['phone'],
        address=data.get('address', self.request.user.customer.home_address),
        restaurant_address=cart_meal.meal.restaurant.address,
    )
    order.cart_meal.set([cart_meal for cart_meal in cart_meals])