To add items to a many-to-many field in Django, you need to use the add() method. Here’s how:
First, retrieve the model instance you want to add items to. For example:
book = Book.objects.get(id=1)
Next, retrieve the items you want to add to the many-to-many field:
authors = Author.objects.filter(id__in=[1, 2, 3])
Finally, add the items to the many-to-many field using the add() method:
book.authors.add(*authors)
Note that the * operator is used to unpack the QuerySet into individual arguments, so that each item in the QuerySet is added as a separate item to the many-to-many field.
Once you’ve added items to a many-to-many field, you can also use other methods like remove() and clear() to manipulate the items in the field.