Strange Python Youtube Statements

I was surfing YouTube and I came across these strange Python statements

n: int xyz
n1: str “Hello World”

What is “n:”?

I Googled it but didn’t find anything about them.

Using Python 3.11.

They look like type annotations for additional static type checking tools. But they also need an assignment operator = after the type and before the value onthe right, to be valid Python syntax.