from django.http import HttpResponse
from django.shortcuts import render_to_response
from store.models import FandomHierarchy

def frontpage(request, filter):
	return render_to_response('index.html', {'filter': filter, 'nodes': FandomHierarchy.objects.all()})

from django.http import HttpResponse
from django.shortcuts import render_to_response
from store.models import FandomHierarchy

def frontpage(request, filter=None):
	return render_to_response('index.html', {'filter': filter, 'nodes': FandomHierarchy.objects.all()})

Add default value for filter so things don't break