models.py

from django.db import models

class Pizza(models.Model):
    #defining pizzas
    name = models.CharField(max_length=100)
    date_added = models.DateTimeField(auto_now_add=True)


    def __str__(self):
        return self.name

class Topping(models.Model):
    name = models.CharField(max_length=100)
    date_added = models.DateTimeField(auto_now_add=True)
    pizza = models.ForeignKey(Pizza,on_delete=models.CASCADE)


    class Meta:
        verbose_name_plural = 'Toppings'