graphene-django/examples/cookbook-plain/cookbook/recipes/models.py

from django.db import models

from ..ingredients.models import Ingredient


class Recipe(models.Model):
    title = models.CharField(max_length=100)
    instructions = models.TextField()
    def __str__(self):
        return self.title


class RecipeIngredient(models.Model):
    recipe = models.ForeignKey(Recipe, related_name='amounts', on_delete=models.CASCADE)
    ingredient = models.ForeignKey(Ingredient, related_name='used_by', on_delete=models.CASCADE)
    amount = models.FloatField()
    unit = models.CharField(max_length=20, choices=(
        ('unit', 'Units'),
        ('kg', 'Kilograms'),
        ('l', 'Litres'),
        ('st', 'Shots'),
    ))