Bayes net inference in Pyro

I am familiar with Bayes nets (discrete/continuous/hybrid). I recently started to learn basics of Pyro and tried to model simple Bayes nets as Pyro programs. I also noticed the simple example answered in Question "Whats the Difference between probabilistic programming such as pyro and Belief networks?".

Can anyone provide a full working Pyro example that shows Bayesian inference for computing any node/variable X posterior distribution P(X|e) in a Bayes net given some set of evidence e? Inference can be exact or approximate. The 3-node example from the mentioned answer would suffice.