Instantiate model instance with manytomany field in Django

Question

I have a method that works, but it seems very clumsy, and I would think there is a better way to do this.

I have a Model that relates a user on my site (a twitter clone for learning purposes) to a list of other users.

Right now when I create a new user, I want to initialize that list with the user as a member of the list.

My model is:

class FollowerList(models.Model)
    follower = models.ForeignKey(User,related_name="follower")
    followed = models.ManyToManyField(User,related_name="followed")

The code in my view that I'm using right now is

user = User.objects.get(username=uname)
flst = FollowerList()
flst.follower = user
flst.save()
flst.followed.add(user)
flst.save()

It seems to me like there should be a method for creating this without calling save() twice, but I can't seem to find it in the docs or anywhere else.

Answer 1

You don't need to call save after the many2many.add()

You could also shorten the code to 2 lines:

flst = FollowerList.objects.create(follower=user)
flst.followed.add(user)

Answer 2

Yuji's answer is correct. You can not add an object to a M2M field until it has been saved. I wanted to mention a shorter way to create instances though.

user = User.objects.get(username=uname)
flst = FollowerList(follower=user) #use key word args to assign fields
flst.save()
flst.followed.add(user)
# don't need to save after adding an object to many to many field.

I find that syntax slightly nicer than creating an empty instance and assigning fields. Though the objects.create() method (mentioned by Yuki) is nicer still.