Caddie is built to use an embeded version of python which is downloaded after installation. Python is not installed on your system, but is extracted to a subfolder \python of the installation folder ( %LOCALAPPDATA%\Programs\RunTime_ToolKit\python ). No system paths are modified to support Python.
Caddie is using Python embeddable version 3.9.2 X64.
The embeded version has the following additional packages installed.
C Runtime is required to support image processing. Caddie requires the X64 runtime only. Download it from Microsoft
You can test your python installation using a session file: The syntax is:
python AnalyzeScreenDiffs.py -s sessionfilepath
ex
C:\Users\Coder\AppData\Roaming\RTTK>python AnalyzeScreenDiffs.py -s C:\Users\Coder\AppData\Roaming\RTTK\SESS\RT_Caddie\2021\3\RTM.RT_Caddie.2021-03-05_18-36-50.rttksess