example_quantitative.py, traffic2 has no transitions
From @gbreysens at Teams:
"I had some trouble with this piece of code (example_quantitative.py). What I'm trying to do is save the traffic and traffic2 objects via pickle. This succeeds for traffic, but later fails for traffic2 when I want to do abstr.TrafficModelLinearPETC.from_bytestream_file('traffic2.pickle') . I cannot check the content of traffic2 either, it returns "Unable to get repr for <class 'ETCetera.Abstractions.LinearPETC.TrafficModelLinearPETC.TrafficModelLinearPETC'>". Transitions2 is also empty, which I did not expect."