Can't get rid of old version of python

[Ciarán Ó Duibhín]

Hi,

On Windows 10, I uninstalled all previous versions of Python and 
installed v3.9.6.

When I use the start menu option Python 3.9 (64-bit), I get the prompt 
"Python 3.9.6" as expected.  The same happens when I type "py" at the 
DOS prompt.

But when I type "python" at the DOS prompt, I get "Python 3.8.10".  I 
don't understand this, as I uninstalled old versions, and I do not see a 
DOS environment variable called "python" anywhere.

The real problem comes when I install a package, e.g. germalemma.  
Python 3.8.10 can use it, but Python 3.9.6 can't find it.

I notice that "site-packages" containing germalemma and its dependencies 
is located in 
...Packages\PythonSoftwareFoundationPython.3.8.qbz5n2kfra8p0\LocalCache\local-packages\Python3.8

Also there is a load of python 3.8 stuff at C:\Program 
Files\WindowsApps\PythonSoftwareFoundation.Python.3.8_3.8.2800.0_x64__qbz5n2kfra8p0 
which directory is virtually inaccessible from Windows but can be listed 
in DOS.

How can I get rid of Python 3.8.10 , and install my packages to 3.9.6?

Ciarán Ó Duibhín