Splunk 8 upgrade python version

Hi Experts, I need to install "Splunk Enterprise Security" and "Splunk ITSI" apps. For this Python 3 is require ??? Mu current splunk version is Splunk 8.0.1 (build 6db836e2fb9e), but python version is : $SPLUNK_HOME/bin/splunk cmd python --version Python 2.7.16 Please guide me how I upgrade splunk python version.