Python - uninstall old version and install latest version

python_install.sh

!#/bin/bash

package_name=python3.5

# Get list of all installed apps
apt list --installed | grep $package_name

# Uninstall old version of Python
apt-get remove $old_package_name

# Install latest version of Python
apt-get install $new_package_name       # apt-get -s runs a simulation of installation process

$pythonVersion

# install MedPy python 2.x
apt-get install python-pip python-numpy python-scipy libboost-python-dev build-essential
pip install nibabel pydicom medpy

# install MedPy python 3.x
apt-get install python3-pip python3-numpy python3-scipy libboost-python-dev build-essential
pip3 install nibabel pydicom medpy