functionGlobalContext: require with @

I am trying to access a standalone library in a function node and the approach shown in generic nodejs examples for the require command looks like this:
const sgMail = require('@sendgrid/mail');

I have added the following (including some other modules which work) to the .node-red folder in settings.js under functionGlobalContext:
sgMail: require('@sendgrid/mail')

and the following at the top of my function node:
var sgMail = global.get("@sendgrid/mail");

Then when this is executed:
sgMail.setApiKey(process.env.SENDGRID_API_KEY);

It returns the following which I think indicates that the sendgrid module never got loaded.
"TypeError: Cannot read property 'setApiKey' of undefined"

Looking for advice and the meaning of the @ character in the require('@sendgrid/mail') syntax.

Any help appreciated. - Thanks in advance.

Edit - This has also been added to the /.node-red folder's package.json file:

"dependencies": {
        "@sendgrid/mail": "^7.2.6",

Node-RED version: v1.1.3
Node.js version: v10.22.0
Linux 5.4.0-1024-gcp x64 LE

You can probably test that the require worked. I suspect that it is the global.get is what fails because of the embedded @ symbol. If so, that is an edge case that will need handling in core. One for Nick or Dave.

I have a similar problem with uibuilder that I've not managed to fix yet.

@christl if you have added sgMail: require('@sendgrid/mail') to the functionGlobalContext value in your settings file, then you would do:

var sgMail = global.get("sgMail");

in your Function node. This is because you are setting the sgMailglobal context value.

Doh! Missed that complexly - blaming lack of coffee input. Will shut down and reboot myself.

Worked. Thank you very much.