Recover GET parameter from PasswordResetConfirmView

I'm trying to recover a GET parameter from the django template view django.contrib.auth.PasswordResetConfirmView. Basically when a user click on his password reset link (like http://127.0.0.1:8000/commons/reset/MQ/4t8-210d1909d621e8b4c68e/?origin_page=/mypage/) I want to be able to retrieve the origin_page=/mypage/ argument. So far my url.py looks like this:

from django.urls import path
from . import views

app_name = 'commons'
urlpatterns = [
    path('reset/<uidb64>/<token>/', views.PasswordResetConfirmView.as_view(), name='password_reset_confirm'),
]

And my views.py like this:

from django.contrib.auth import views as auth_views

class PasswordResetConfirmView(auth_views.PasswordResetConfirmView):
    template_name = 'commons/password_reset_confirm.html'
    success_url = '/commons/reset/done/'

    def get(self, request, *args, **kwargs):
        self.extra_context = {
            'origin_page': self.request.GET['origin_page']
        }
        return super().get(request, *args, **kwargs)

As you can see I'm trying to get my origin_page with 'origin_page': self.request.GET['origin_page'] but it doesn't work. It throws me a MultiValueDictKeyError. I even used the debugger to inspect every objects from the class/method but none of them seems to contains my origin_page variable. Any idea? Thanks