Django 1.5, python 2.6
The model automatically creates a user under certain conditions:
User.objects.get_or_create(username=new_user_name, is_staff=T
Andrew M. Farrell's answer is correct. I only add the use of get_user_model() and a full example.
from django.contrib.auth import get_user_model
from django.contrib.auth.models import Permission
u = get_user_model().get(username=new_user_name)
To get the permission you can use
permission = Permission.objects.get(name='Can view poll')
or
permission = Permission.objects.get(codename='can_view_poll')
then add it to the user permissions set
u.user_permissions.add(permission)
Use add and remove methods:
from django.contrib.auth.models import Permission
permission = Permission.objects.get(name='Can view poll')
u.user_permissions.add(permission)