Please recommend an example on the membership form of the Django project.

The advantage of Django is that it basically includes the user model. So if you create a Jango project, you can get an admin right away and manage users and models in the admin.

I'm sorry it's an English document, but I recommend the following example that Jango provides as a standard.

https://docs.djangoproject.com/en/1.8/topics/auth/default/#django.contrib.auth.views.login