I created a simplified version. of the simple discrete HMM numpyro example for Bach chorales, and put it in this colab. However, when i run it, I get the error `module 'funsor' has no attribute 'interpretations'`

. Full stack trace below.

```
INFO:__main__:Starting inference...
---------------------------------------------------------------------------
UnfilteredStackTrace Traceback (most recent call last)
<ipython-input-16-f7707504f100> in <module>()
15 nstates = 5
---> 16 mcmc.run(rng_key, sequences, lengths, hidden_dim=nstates)
17 mcmc.print_summary()
57 frames
UnfilteredStackTrace: AttributeError: module 'funsor' has no attribute 'interpretations'
The stack trace below excludes JAX-internal frames.
The preceding is the original exception that occurred, unmodified.
--------------------
The above exception was the direct cause of the following exception:
AttributeError Traceback (most recent call last)
/usr/local/lib/python3.7/dist-packages/numpyro/contrib/funsor/infer_util.py in compute_markov_factors(time_to_factors, time_to_init_vars, time_to_markov_dims, sum_vars, prod_vars, history, sum_op, prod_op)
120 # we eliminate all plate and enum dimensions not available at markov sites.
121 eliminate_vars = (sum_vars | prod_vars) - time_to_markov_dims[time_var]
--> 122 with funsor.interpretations.lazy:
123 lazy_result = funsor.sum_product.sum_product(
124 sum_op,
AttributeError: module 'funsor' has no attribute 'interpretations'
```