how to install postgresql 12 on ubuntu code example

Example 1: ubuntu install postgresql 12

sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt $(lsb_release -cs)-pgdg main" > /etc/apt/sources.list.d/pgdg.list'
wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
sudo apt-get update
sudo apt-get -y install postgresql

Example 2: install postgres 11 ubuntu

sudo apt update && sudo apt -y upgrade

wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -

RELEASE=$(lsb_release -cs)
echo "deb http://apt.postgresql.org/pub/repos/apt/ ${RELEASE}"-pgdg main | sudo tee  /etc/apt/sources.list.d/pgdg.list

cat /etc/apt/sources.list.d/pgdg.list

sudo apt update

sudo apt -y install postgresql-11

sudo -u postgres psql

postgres=# CREATE USER wcl WITH PASSWORD 'wclPassword';
postgres=# CREATE DATABASE wcl;
postgres=# ALTER USER wcl WITH SUPERUSER;
postgres=# exit