def login_view(request):
    form = AuthenticationForm()
    if form.is_valid():
        if request.POST:
            username = request.POST['username']
            password = request.POST['password']
            user = authenticate(username=username, password=password)
            if user is not None:
                login(request, user)
                messages.success(request, 'You have successfully logged in.')
                return HttpResponseRedirect('/profile/')
        else:
            form = AuthenticationForm()
    return render(request, 'accounts/login.html', {'form': form})