'Determine the lookups we want to use'

def lookups(self, request, model_admin):

    path_values = Page.objects.order_by('path').values_list('path', flat=True)
    path_set = []
    for v in path_values:
        if (v == ''):
            path_set.append(('', '/'))
        else:
            parts = v.split('/')[:2]
            new_value = '/'.join(parts)
            new_tuple = (new_value, new_value)
            if (new_tuple not in path_set):
                path_set.append((new_value, new_value))
    return path_set
