def rejestracja(request):
    username = ''
    email= ''
    password = ''
    username = request.POST.get('username')
    email = request.POST.get('email')
    password = request.POST.get('password')
    if request.method == 'POST':
        if not (User.objects.filter(username=username).exists() or User.objects.filter(email=email).exists()):
            User.objects.create_user(username, email, password)
            user = authenticate(username = username, password = password)
            login(request, user)
            return HttpResponseRedirect('/')
        else:

            raise forms.ValidationError("Looks like a user with that username or email already exists")

    return render(request, 'rejestracja.html')