I ran into some problems which I detailed in issue #99

I ran into some problems which I detailed in issue 99, https://github.com/jsonpickle/jsonpickle/issues/99. I was pulling models out of SqlAlchemy and some of the sub-classes were not iterable, so I went through and added if/else blocks where I was facing problems. This now works for me, without any obvious errors.
I see what you're doing here, and it's not bad. However, I think the right thing would be to diagnose why execution ends up here, because sequence objects should always have an iter methods.