AttributeError: 'Prophet' object has no attribute 'stan_backend' solution

I encountered the following problem when using Facebook prophet:
The code is as follows:

from prophet import Prophet
model = Prophet()

The following error is reported when executing the program:

	  File "D:\Python\Python38\lib\site-packages\prophet\forecaster.py", line 156, in _load_stan_backend
	    logger.debug("Loaded stan backend: %s", self.stan_backend.get_type())
	AttributeError: 'Prophet' object has no attribute 'stan_backend'

The running environment is windows server 2019, python3.8.

Package             Version
------------------- ----------
APScheduler         3.10.1
backports.zoneinfo  0.2.1
certifi             2023.5.7
charset-normalizer  2.0.12
cmdstanpy           1.1.0
colorama            0.4.6
convertdate         2.4.0
cycler              0.11.0
ephem               4.1.4
greenlet            2.0.2
h5py                3.8.0
holidays            0.28
idna                3.4
imageio             2.31.1
importlib-metadata  4.11.3
importlib-resources 5.12.0
joblib              1.1.0
kiwisolver          1.4.4
loguru              0.7.0
LunarCalendar       0.0.9
matplotlib          3.4.3
networkx            3.1
numpy               1.22.4+mkl
packaging           23.1
pandas              1.4.3
Pillow              8.4.0
pip                 21.1.1
prophet             1.1.4
PyMeeus             0.5.12
pyparsing           3.1.0
python-dateutil     2.8.2
pytz                2022.1
PyWavelets          1.4.1
scikit-image        0.19.2
scikit-learn        1.1.1
scipy               1.7.3
setuptools          56.0.0
six                 1.16.0
threadpoolctl       3.1.0
tifffile            2023.7.4
tqdm                4.65.0
tzdata              2023.3
tzlocal             5.0.1
urllib3             1.26.16
win32-setctime      1.1.0
zipp                3.15.

This error is in python. The facebook prophet object does not have the "stan_backend" attribute. It is usually caused by the stan backend not being installed correctly when installing prophet. The solution is to install pystan:

pip install -i https://pypi.tuna.tsinghua.edu.cn/simple pystan==2.19.1.1

My operation is to uninstall cmdstanpy and prophet first:
pip uninstall cmdstanpy
pip uninstall prophet
pip install -i https://pypi.tuna.tsinghua.edu.cn/simple pystan==2.19.1.1
pip install -i https:// pypi.tuna.tsinghua.edu.cn/simple prophet

Reference: https://github.com/facebook/prophet/issues/1835

	Just adding my two cents to this issue:
	The documentation mentions that we need to install a specific version of PyStan, so be mindful of this.
	pip install pystan==2.19.1.1
	After installing this it started working for me

It's strange. My development environment is Windows 10 Professional Edition, and there is no problem in the same installation environment. why?

I don't have pyspan installed on my computer, and there is no problem. Why? Feedback welcome, thank you!