Why is my custom Python script failing during compilation?

Description

Due to a problem with the Quartus® Prime Pro Edition Software version 25.1 and earlier, you might see some Quartus® Prime-related "SET PYTHONHOME" and "PREFIX PYTHONPATH" messages in the console. After these messages, you might see your custom Python scripts fail execution. 

Resolution

To avoid this problem, unset the PYTHONHOME and PYTHONPATH environment variables on the TCL script before calling the Python script. For example: 

unset env(PYTHONHOME)

unset env(PYTHONPATH)

exec python3 my_script.py

This problem is scheduled to be fixed in a future version of the Quartus® Prime Pro Edition Software.