Use the correct user model when creating users

users/forms.py

@@ -1,8 +1,10 @@
-from django.contrib.auth.models import User
+from django.contrib.auth import get_user_model
 from django.contrib.auth.forms import UserCreationForm
 from django import forms
 from django.conf import settings
 
+User = get_user_model()
+
 
 class CreateUserForm(UserCreationForm):
     key = forms.CharField(