**extra_fields argument in Django

Question

I'm trying to create a custom user model in Django using this article

And there a model manager given in this article as :

from django.contrib.auth.base_user import BaseUserManager
from django.utils.translation import ugettext_lazy as _


class CustomUserManager(BaseUserManager):
    """
    Custom user model manager where email is the unique identifiers
    for authentication instead of usernames.
    """
    def create_user(self, email, password, **extra_fields):
        """
        Create and save a User with the given email and password.
        """
        if not email:
            raise ValueError(_('The Email must be set'))
        email = self.normalize_email(email)
        user = self.model(email=email, **extra_fields)
        user.set_password(password)
        user.save()
        return user

    def create_superuser(self, email, password, **extra_fields):
        """
        Create and save a SuperUser with the given email and password.
        """
        extra_fields.setdefault('is_staff', True)
        extra_fields.setdefault('is_superuser', True)
        extra_fields.setdefault('is_active', True)

        if extra_fields.get('is_staff') is not True:
            raise ValueError(_('Superuser must have is_staff=True.'))
        if extra_fields.get('is_superuser') is not True:
            raise ValueError(_('Superuser must have is_superuser=True.'))
        return self.create_user(email, password, **extra_fields)

What I dont understand is **extra_fields passed as argument in the create_user and create_superuser function.

What is **extra_fileds ??What is the purpose of it and what it is doing here??

Thanks in advance!!

May I kindly suggest you do the full [official Python tutorial](https://docs.python.org/3/tutorial/index.html) ? — bruno desthuilliers, Apr 20 '20 at 07:07

Prateek Gupta · Accepted Answer · 2020-04-26T18:59:53.697

**extra_fields is used so that any number of keywords argument (kwarg) can be passed to both the functions create_user and create_superuser.So if the arguments passed to the create_user and create_superuser are there in the associated Custom user model then a user model will be created with all that information.

It is also used to access the built-in fields of the default user model such as is_superuser,is_staff and is_active and assigned them a default value

score 1 · Answer 2 · answered Apr 20 '20 at 05:58

This is known as kwarg, it allows you to pass arbitrary number of keyword argument. So in your case you can pass any other fields to function and it will be save in your model if they exists with same name.

Check out this SO: What is the purpose and use of **kwargs?

score 1 · Answer 3 · answered Apr 20 '20 at 06:02

As per method documentation mentioned here:

The ``extra_fields`` keyword arguments are passed through to the
:class:`~django.contrib.auth.models.User`’s ``__init__`` method to
allow setting arbitrary fields on a :ref:`custom user model

Basically it is same as what any arbitrary keyword arguments in any function. You can pass any keyword arguments through create_user or create_superuser method, and User instance will be created based on those arguments(if they exist in User model).

**extra_fields argument in Django

3 Answers3