class TypeOfIngredient(models.Model):
    name = models.CharField(max_length=200,unique=True,null=False)
    slug = models.SlugField(unique=True)

class Ingredient(models.Model):
    name = models.CharField(max_length=200,unique=True,null=False)
    slug = models.SlugField(unique=True)
    typeofingredient = models.ForeignKey(TypeOfIngredient, related_name='typeof_ingredient',null=True, blank=True,on_delete=models.PROTECT)

class IngredientListSerializer(ModelSerializer):
    class Meta:
        model = Ingredient
        fields = '__all__'

"results": [
        {
            "id": 1,
            "name": "adrak",
            "slug": "adrak",
            "typeofingredient": null
        },
        {
            "id": 2,
            "name": "banana",
            "slug": "banana",
            "typeofingredient": 1
        },

class IngredientListSerializer(ModelSerializer):
    class Meta:
        model = Ingredient
        fields = '__all__'
        depth = 1

"results": [
        {
            "id": 1,
            "name": "adrak",
            "slug": "adrak",
            "typeofingredient": null
        },
        {
            "id": 2,
            "name": "banana",
            "slug": "banana",
            "typeofingredient": {
                    "id": 1,
                    "name": "fruit",
                    "slug": "fruit"
            }
        },