forms.py

   from django import forms
   from django.contrib.auth.models import User
   from django.contrib.auth.forms import UserCreationForm
                                   
   class UserRegistrationForm(UserCreationForm):
       email = forms.EmailField()
                                       
       class Meta:
           model = User
           fields = ['username', 'email', 'password1', 'password2']
        
        

views.py

   from django.contrib import auth
   from django.http import HttpResponse
   from .forms import UserRegistrationForm
   from django.contrib.auth import authenticate
   from django.shortcuts import render, redirect
   
   def register(request):
       if request.method == 'POST':
           form = UserRegistrationForm(request.POST)
           if form.is_valid():
               form.save()
               return redirect('login')
       else:
           form = UserRegistrationForm()
       return render(request, 'register.html', {'form': form})
   
   def login(request):
       if request.method == 'POST':
           username = request.POST['username']
           password = request.POST['password']
           user = authenticate(username=username, password=password)
           if user is not None:
               if user.is_active:
                   auth.login(request, user)
                   return redirect('profile')
       return render(request, 'login.html')
   
   def profile(request):
       return render(request, 'profile.html')
    
    

urls.py

   from app import views
   from django.urls import path
   from django.contrib import admin
   
   urlpatterns = [
       path('admin/', admin.site.urls),
       path('register/', views.register, name='register'),
       path('login/', views.login, name='login'),
       path('profile/', views.profile, name='profile')
   ]

1. 新建register.html, login.html, profile.html

2. 並在<input>中的name的值必須是 'username', 'email', 'password1', 'password2'，或是可以使用Django內建的Template {{ form.as_p }}來完成register所有的<input>和submit button

3. 最後別忘了在HTML加上{% csrf_token %}
可以在Django的管理員頁面127.0.0.1/admin中，看到註冊用戶的username和email