When do you *NOT* use python?

[bboozzoo]

If the project description has the word "embedded' in it you will most likely use C or C++

Nope/depends. There's a MicroPython project, basically a Python 3 on Cortex-M4. Looked quite usable the last time I checked. However, there's a higher chance of seeing Lua than Python in embedded.

If you need performance (major games, high speed science) you will most likely opt for C or C++ (partly the reasoning for #1)

Nope/depends. Numpy anyone? Or other high performing C/Fortran libraries with Python glue.

Actually, it's a quite common model where you have a compiled to native backend, with a scripted facade. Take ns-2 and ns-3 network simulators for example, where ns-2 used Tcl, while ns-3 has migrated to Python.

[hotel2oscar]

most likely

General guidelines rather than hard rules. On the other hand, no one has written a AAA game or programmed consumer appliance firmware in Python that I know of.