JSON document has an improper structure

I’m running the code in the getting started page, using pystan 3.7.0. I’m getting the following error:

ImportError: /some_path/.cache/httpstan/4.10.1/models/cn7mxp6s/stan_services_model_cn7mxp6s.cpython-38-x86_64-linux-gnu.so: undefined symbol: _ZNSt19basic_ostringstreamIcSt11char_traitsIcESaIcEEC1Ev

File simdjson/csimdjson.pyx:452, in csimdjson.Parser.parse()

ValueError: The JSON document has an improper structure: missing or superfluous commas, braces, missing keys, etc.

Any suggestion?

Looks like the program compilation has somehow failed.

How did you install pystan and what operating system do you have?

For mac m1 and m2 users there are instructions how to build httpstan from source