There is currently no way to have a Python for Advanced Analytics engine running under TIBCO Spotfire Statistics Services (TSSS), as we do not expose the APIs for this type of extension. 

However, either the "reticulate" package or the "rPython" package from the open-source R community's Comprehensive R Archive Network (CRAN) repository can be used to make calls out to Python for Advanced Analytics, from either a  TIBCO Enterprise Runtime for R (TERR) engine or an open-source R engine. 

These user-contributed CRAN packages can be downloaded and installed from the CRAN repository, which is found at  https://cran.r-project.org/

Update:  There is now a custom solution available from the TIBCO Community that allows users to run Python directly from a data function in the Spotfire installed desktop client (Spotfire Analyst or Spotfire Desktop).  See the link in this article's Reference section for more details about this "PyDf" custom Spotfire extension.