python manage.py shell

>>> from django.contrib.auth.models import User
>>> u=User.objects.get_or_create(username="testuser2",password="123")
>>> u
(<User: testuser2>, True)

from django.contrib.auth.models import User
user, created = User.objects.get_or_create(username="testuser2")
user.set_password('123')
user.save()