Follow the pyplanet install guide
In addition you'll need mysql-compatible database, currently for linux that is mariadb, unless you choose to select postgres.
$ sudo apt update
$ sudo apt install mariadb-server
$ sudo mysql_secure_installation
$ mariadb -u root -p> CREATE DATABASE pyplanet CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
> CREATE USER pyplanet@localhost IDENTIFIED BY 'your_generated_password';
> GRANT ALL PRIVILEGES ON pyplanet.* TO 'pyplanet'@'localhost';
> exit;