Cannot perform any bayesian test with Abracadabra

[FrancoT1994]

I have been trying to recreate an example of a Bayesian test from the documentation. And every single time, regardless of whether the variables are discrete or continuous, that I try to do a Bayesian test, it keeps running forever.
Here's the code:
`from abra.utils import generate_fake_observations
from abra import Experiment, HypothesisTest

experiment_observations = generate_fake_observations(
distribution='bernoulli', # binary data
n_treatments=2,
n_attributes=0,
n_observations=1000
)

exper = Experiment(data=experiment_observations, name="Demo Experiment")

ab_test = HypothesisTest(
metric="metric",
treatment="treatment",
control="A", variation="B",
hypothesis="larger",
inference_method="proportions_delta"
)

bayesian_ab_test = ab_test.copy(inference_method='beta_binomial')

bayesian_gaussian_ab_test_results = exper.run_test(ab_test, alpha=0.5)

assert bayesian_gaussian_ab_test_results.accept_hypothesis
bayesian_gaussian_ab_test_results.display()`

Every time the debugger reaches the inference_method="beta_binomial" part, it keeps running forever.
Another message that I get is:

INFO:pystan:COMPILING THE C++ CODE FOR MODEL anon_model_d34187aab5ea62cad0497fb05b663314 NOW.
/Users/francot/PycharmProjects/pythonProject1/lib/python3.8/site-packages/Cython/Compiler/Main.py:369: FutureWarning: Cython directive 'language_level' not set, using 2 for now (Py2). This will change in a later release! File: /var/folders/qt/mb7944ws4bb54pdyx3vwnn6cz_jcx4/T/tmpfcnkebb1/stanfit4anon_model_d34187aab5ea62cad0497fb05b663314_477032182280377507.pyx
tree = Parsing.p_module(s, pxd, full_module_name)

What could this be?
Thanks in advance!