Python version on the HP Prime

[Thomas_Sch]

It's Micropython.
See e.g. https://www.hpmuseum.org/forum/thread-16862.html
From the build in help (start the python app, then press Help), page 2:
"HPPrime uses micropython 3.4. (You should be able to find all the documentation at https://micropython.org/). "
Micropython uses only a subset of python.

sunmoon (Sun and Moon Almanac 0.92 by H. Umland) maybe uses functions net contained in micropython, and/or you need to include other libraries.

Edit: In the full Help go to "Tree", "Search", "Python all_modules",
there all all available modules listed. (builtins, micropython, uarray, uio, ...)