how to get the instance of a newly created user in django function based view

Question

i'm writing the logic in django where a newly created user would automatically get the free membership when they hit the signup button and right now, i know what to do but i don't know how to implement maybe becuase i don't have much experince with django. i defined an instance variable to store all the newly created information but i'm just stock and it keeps showing red underlined word in vsCode, Any help would be greatly appreciated

views.py

def register(request):
    reviews = Review.objects.filter(status='published')
    info = Announcements.objects.all()
    categories = Category.objects.all()
    if request.method == "POST":
        form = UserRegisterForm(request.POST)
        if form.is_valid():
            form.save()
            username = form.cleaned_data.get('username')
            obj = request.user
            get_membership = Membership.objects.get(membership_type='Free')
            # error is showing "instance" is not access using visual studio code
            instance = UserMembership.objects.create(user=obj, membership=get_membership)

            messages.success(request, f'Account Successfully created for {username}! You can Login In Now')
            return redirect('userauths:login')
    elif request.user.is_authenticated:
            return redirect('elements:home')
    else:
        form = UserRegisterForm()
    context = {
        'reviews': reviews,
        'form': form,
        'info': info,
        'categories': categories
    }
    return render(request, 'userauths/register.html', context)