run the tree command in terminal code example

Example 1: osx tree

osx doesn't have tree, install by:
brew install tree

Example 2: terminal tree command

# yum install tree	 #RHEL/CentOS 7
# dnf install tree	 #Fedora 22+ and /RHEL/CentOS 8
$ sudo apt install tree	 #Ubuntu/Debian
# sudo zypper in tree 	 #openSUSE