register: use ModelForm, and print all errors

accounts/urls.py

@@ -1,9 +1,10 @@
 from django.urls import path
 
-from .views import login, register, delete, change_password
+from .views import login, logout, register, delete, change_password
 
 urlpatterns = [
     path("login", login.LoginView.as_view(), name="login"),
+    path("logout", logout.LogoutView.as_view(), name="logout"),
     path("register", register.RegisterView.as_view(), name="register"),
     path("delete", delete.DeleteView.as_view(), name="delete"),
     path("change_password", change_password.ChangePasswordView.as_view(), name="change_password"),