Django - Best way to create custom User models

readme.md

1. Don't use auth as app name. It is already used by Django for default User model.
2. Overwrite default User in settings.py. If auth_email is what you named this app, then put this in settings.py:-

AUTH_USER_MODEL = 'auth_email.User'

admin.py

from django.contrib import admin
from django.contrib.auth.admin import UserAdmin as DefaultUserAdmin

from .models import User


class UserAdmin(DefaultUserAdmin):
    model = User

    fieldsets = (
        (None, {'fields': ('email', 'password')}),
        (('Personal info'), {'fields': ('first_name', 'last_name')}),
        (('Permissions'), {'fields': ('is_active', 'is_staff', 'is_superuser',
                                      'groups', 'user_permissions')}),
        (('Important dates'), {'fields': ('last_login', 'date_joined')}),
    )

    add_fieldsets = (
        (None, {
            'classes': ('wide',),
            'fields': ('email', 'password1', 'password2'),
        }),
    )

    list_display = ('email', 'first_name', 'last_name', 'is_staff')
    search_fields = ('email', 'first_name', 'last_name')
    ordering = ('email',)


admin.site.register(User, UserAdmin)

models.py

from django.db import models
from django.contrib.auth.models import AbstractUser, BaseUserManager


class UserManager(BaseUserManager):
    use_in_migrations = True

    def _create_user(self, email, password, **extra_fields):
        """
        Create and save a user with the given email and password.
        """
        if not email:
            raise ValueError('email must be set')
        email = self.normalize_email(email)
        user = self.model(email=email, **extra_fields)
        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_user(self, email, password=None, **extra_fields):
        extra_fields.setdefault('is_staff', False)
        extra_fields.setdefault('is_superuser', False)
        return self._create_user(email, password, **extra_fields)

    def create_superuser(self, email, password, **extra_fields):
        extra_fields.setdefault('is_staff', True)
        extra_fields.setdefault('is_superuser', 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)


class User(AbstractUser):
    username = None
    email = models.EmailField(
        unique=True,
        error_messages={
            'unique': 'This email is already being used for another account.',
        },
    )

    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = []
    objects = UserManager()