model fit works when running on shell, but runs into error when executing as script

[tyjchen]

i'm trying to build a bayes model object using the survivalstan package, the model object compiles properly when the script below is executed directly on a python shell (copy + paste method into the interpreter). however, when I execute the entire script at once using the command line format, I get a variable error (see below)

File "C:\ProgramData\Anaconda3\lib\runpy.py", line 85, in _run_code
exec(code, run_globals)
File "C:\Users\thomasc\Documents\WeibullMethod\weibull_bayes_demo.py", line 117, in
model = main()
File "C:\Users\thomasc\Documents\WeibullMethod\weibull_bayes_demo.py", line 112, in main
make_inits = survivalstan.make_weibull_survival_model_inits)
File "C:\ProgramData\Anaconda3\lib\site-packages\survivalstan-0.1.2.8-py3.7.egg\survivalstan\survivalstan.py", line 167, in fit_stan_survival_model
File "C:\ProgramData\Anaconda3\lib\site-packages\stanity-0.1.4-py3.7.egg\stanity\fit.py", line 37, in fit
File "C:\ProgramData\Anaconda3\lib\site-packages\pystan\api.py", line 447, in stan
n_jobs=n_jobs, **kwargs)
File "C:\ProgramData\Anaconda3\lib\site-packages\pystan\model.py", line 813, in sampling
ret_and_samples = _map_parallel(call_sampler_star, call_sampler_args, n_jobs)
File "C:\ProgramData\Anaconda3\lib\site-packages\pystan\model.py", line 87, in _map_parallel
pool.close()

how can I prevent this error? I do not wish to have to interact with a python shell directly to train a model.
code below to train model, directly same as the example code for this package
this compiles if copy and pasted directly into a shell, but fails if saved as a .py script and executed from command line as python <script name>

import survivalstan
import stanity
import seaborn as sb
import matplotlib.pyplot as plt
import statsmodels
dataset = statsmodels.datasets.get_rdataset(package = 'survival', dataname = 'flchain' )
d = dataset.data.query('futime > 7')
d.reset_index(level = 0, inplace = True)
testfit_wei = survivalstan.fit_stan_survival_model(model_cohort = 'Weibull model', model_code = survivalstan.models.weibull_survival_model, df = d, time_col = 'futime', event_col = 'death', formula = 'age + sex', iter = 3000, chains = 4, make_inits = survivalstan.make_weibull_survival_model_inits)