Mongoose type Map to Apollo GraphQL Scalar Type

Question

How to Modular a Mongoose Map to a valid type for Apollo-GraphQL Server?

I provided an Example. Basically, a Map is a Key Value list. Is something like this accomplished with interfaces?

Example:

Mongoose Schema

const userSchema = new Schema({
   Financials: {
        type: Map,
        of: new Schema({
            q1: {},
            q2: {},
        })
   }
});

As a Document

{
   "Financials":{
      "2019":{
         "q1":{  },
         "q2":{  }
      },
      "2012":{
         "q1":{  },
         "q2":{  }
      }
   }
}

const typeDefs = gql `
      type Financials {
      }
    `