from django.shortcuts import _get_queryset

def get_obj_or_none(klass, *args, **kwargs):
    queryset = _get_queryset(klass)
        try:
	    return queryset.get(*args, **kwargs)
	except:
	    return None

def get_list_or_none(klass, *args, **kwargs):
    queryset = _get_queryset(klass)
    obj_list = list(queryset.filter(*args, **kwargs))
    if not obj_list:
        return None
    return obj_list