Switch Php version

sudo a2dismod php7.2 
sudo a2enmod php5.6
sudo service apache2 restart

OR


sudo update-alternatives --set php /usr/bin/php5.6
sudo update-alternatives --set phar /usr/bin/phar5.6
sudo update-alternatives --set phar.phar /usr/bin/phar.phar5.6
sudo update-alternatives --set phpize /usr/bin/phpize5.6
sudo update-alternatives --set php-config /usr/bin/php-config5.6

How to install python 3.6 in ubuntu

  1. Open terminal using keyboard ctrl+alt T
  2. sudo add-apt-repository ppa:jonathonf/python-3.6
  3. sudo apt-get update
  4. sudo apt-get install python3.6
  5. sudo update-alternatives –install /usr/bin/python3 python3 /usr/bin/python3.5 1
  6. sudo update-alternatives –install /usr/bin/python3 python3 /usr/bin/python3.6 2
  7. sudo update-alternatives –config python3
  8. python3 -V then show : Python 3.6.1+