Lumen, How to load a file that is out of the project

I have a pdf file inside the documents folder of my user, which I need to return through a route. For this I wrote the following simple function

public function showPdf(){
    return response()->file('/home/victor/Documents/1-39-1.pdf');
}

But when I call this function through a GET, the browser returns the following exception

Method LaravelLumenHttpResponseFactory::file does not exist.

How can I tell lumen that my file is on that path?

Answer

In lumen 7.x this method is named download and can be seen here. This is fairly similar to Laravels file(), therefor this change should work.

return response()->download('/home/victor/Documents/1-39-1.pdf');