choose and open a folder in Windows

[palo]

Hello
I wrote a little script (that will be used only under Windows if at
all) where the user should choose a directory and the script will then
process some data files in the directory and write the result there. To
make it a bit more pleasant, it would be nice if the directory were
chosen by the standard win directory chooser. When the script is done,
it could open the the directory, so that the user can check the
results. How to do these two things? (I searched this forum and found a
simple solution for the first one, using Tkinter - so there is just an
unimportant question whether one really needs Tkinter to start a
standard windows dialog. But I didn't find how to make windows to open
a given directory in file expolorer)
P.