RuntimeError: Type 'Tuple when using Deep Markov Model

I am trying to use deep Markov Model on my dataset. However, when I use it I get the following run time error:

I don’t even know what this error means. My code is exactly the same as:
https://github.com/pyro-ppl/pyro/blob/dev/examples/dmm/dmm.py

Could someone explain what possibly could be causing this error? Insights are appreciated.

are you using the --jit flag?

Yes I was. But now I’m using trace_elbow instead of jitTrace_Elbow and the code works now. But I don’t quite understand why jitTrace_elbow didn’t work. Insights into will be appreciated.