When using two version of the python (2 and 3) on windows 10 and you need to make one of the versions "main" version. By main version I mean when you call "python" in cmd your main version will open. To run this script you need some kind of "linux on windows" system, like MinGW. To add both pythons to your windows PC you can follow this tutorial h…

python_master.sh

#!/bin/bash

#change the dots with your python 2 and 3 paths and leave .exe file names as they are, you can find them in windows env variables
#python2 path
py2=../python.exe
py2_n=../python2.exe 
#python3 path
py3=../python.exe
py3_n=../python3.exe

VERSION=$1
echo python master change the python version for python.exe
#echo $VERSION
#if no parameter ask for it
if [ -z $VERSION ]
then
	echo which version you want to be main 2 or 3
	read VERSION
	echo you chose version $VERSION
else	
	echo you chose version $VERSION
fi

if [[ $VERSION -ne '2' ]] && [[ $VERSION -ne '3' ]]
then
	echo wrong verson
	exit 1
fi

#find current main version
if [ -f "$py2" ]
then
    echo "python 2 is main"
elif [ -f "$py3" ]
then
    echo "python 3 is main"
else
	echo there is a problem with versions
	exit 1
fi

#change verson
#version 2 main
if [[ $VERSION -eq '2' ]] && [[ -f "$py3" ]]
then
	mv $py3 $py3_n
	mv $py2_n $py2
elif [[ $VERSION -eq '3' ]] && [[ -f "$py2" ]]
then
	mv $py2 $py2_n
	mv $py3_n $py3
else
	echo version $VERSION is already main
fi