How to put the login and password from the User model in Yii2 into a separate file?

Question

Yii

Here I look basicly from the box here the login and password are registered

public $authKey;
    public $accessToken;

    private static $users = [
        '100' => [
            'id' => '100',
            'username' => 'admin',
            'password' => 'admin',
            'authKey' => 'test100key',
            'accessToken' => '100-token',
        ],
        '101' => [
            'id' => '101',
            'username' => 'demo',
            'password' => 'demo',
            'authKey' => 'test101key',
            'accessToken' => '101-token',
        ],
    ];

https://github.com/yiisoft/yii2-app-basic/blob/mas...

This is not very convenient. I wanted to put it in params. But when calling Yii::$app->params['user'] it throws an error.
Who solved this problem?