Importing from Meteor core modules

Hey guys,

After recently making the switch to 1.3 and installing ESLinst, my IDE is complaining about several things not being defined.

E.g. Products = new Mongo.Collection('products'); gets me Mongo is not defined.
Same with const player = _.find..., I get '_' is not defined.

At the top of my file, I have import { Meteor } from 'meteor/meteor';, but where would I put underscore and Mongo? Where are they exported?