Add get_object_or_none to django.shortcuts

[Alexey Rogachev]

Quite often we need to find object of certain model and return None if it does not exist. I suggest to add this to django.shortcuts similar to get_object_or_404:

def get_object_or_none(klass, *args, **kwargs):
    queryset = _get_queryset(klass)
    try:
        return queryset.get(*args, **kwargs)
    except queryset.model.DoesNotExist:
        return None

Yes, we can easily create this in our own code, but maybe consider to add this to the core?