Why takes ManyToManyField on save?

Question

Django

Hello everyone , the
problem is that when
from django.db import models
from apps.product.models import Product
from apps.core.models import Category
class CategoryConverter(models.Model):
product = models.ManyToManyField(Product, blank=True, null =True)
category = models.ForeignKey(Category, blank=True, null=True)
def save(self, *args, **kwargs):
print(self.category)
print(self.product)
if self.product and self .category:
for product in self.product.all():
product.category.add(self.category)
product.save()
return super(CategoryConverter, self).save(*args, **kwargs)
I select products in the admin but when saving self.product is empty Thank you in
advance )

Answer 1

• need to post the code in the question
• why is save overridden for this purpose, why is ModelForm not used?
• the manytomany field is filled only for existing objects, that is, you must first save the object, and then add categories to it

In addition, there are obvious errors in the code. The loop adds objects to the ForeignKey field, etc.