How to use mysqli class in own class with namespace?

Question

PHP

How to use mysqli class in own class with namespace?
The question is in the title.
If anyone knows how to do this I would be grateful.
A little more detail:
There is a class that uses a namespace. In its constructor there is a connection to the database, which is done something like this
$mysqli = new mysqli($sr, $lg, $ps, $tb);

Answer 1

new \mysqli...