$ sudo apt-get update
$ sudo apt-get install build-essential tk-dev libncurses5-dev libncursesw5-dev libreadline6-dev libdb5.3-dev libgdbm-dev libsqlite3-dev libssl-dev libbz2-dev libexpat1-dev liblzma-dev zlib1g-dev
$ wget https://www.python.org/ftp/python/3.6.5/Python-3.6.5.tar.xz
$ tar xf Python-3.6.5.tar.xz
$ cd Python-3.6.5
$ ./configure
$ make
$ sudo make altinstall