from catalog.views import catalog_products_view
urlpatterns = patterns('', url('^(?P<category>[\\w-]+)/$',
    catalog_products_view, name='catalog_products_view'), url(
    '^(?P<category>[\\w-]+)/(?P<filter1>[\\w-]+)/$', catalog_products_view,
    name='catalog_products_view'), url(
    '^(?P<category>[\\w-]+)/(?P<filter1>[\\w-]+)/(?P<filter2>[\\w-]+)/$',
    catalog_products_view, name='catalog_products_view'), url(
    '^(?P<category>[\\w-]+)/(?P<filter1>[\\w-]+)/(?P<filter2>[\\w-]+)/(?P<filter3>[\\w-]+)/$'
    , catalog_products_view, name='catalog_products_view'))
Django: variable parameters in URLconf