Why is there a "default" key in node json response? - node.js

Question

As in the image, i am not sending any additional "Default" key but it is rendering
the whole json data as response again inside "default" key.
and i don't want it
what can be the reason for this ?
how can this be removed?"
here is the code snippet
import express from 'express'
import * as StateData from '../shared/indian_city_and_states.json';
import * as cuisines from '../shared/cuisines.json';
class MasterDataController {
public path: string="/master_data";
public router=express.Router();
constructor() {
this.intializeRoutes()
}
public intializeRoutes() {
this.router.get(`${this.path}/geo_data_list`,this.getRestaurants);
this.router.get(`${this.path}/cuisines_list`,this.getCuisines);
}
getRestaurants=async (
request: express.Request,
response: express.Response
) => {
return response.json(StateData)
}
getCuisines = (
request: express.Request,
response: express.Response
)=>{
return response.json(cuisines)
}
}
export default MasterDataController;
Here is what i am getting in response
{
"cuisines": [
"Bakery and Bread",
"Meat and Seafood",
"Pasta and Rice",
"Oils, Sauces, Salad Dressings, and Condiments",
"Cereals and Breakfast Foods",
"Soups and Canned Goods",
"Frozen Foods",
"Dairy, Cheese, and Eggs",
"Snacks and Crackers",
"Desserts",
"Beverages",
"Ice Cream",
"Fast foods",
"Coffee"
],
"default": {
"cuisines": [
"Bakery and Bread",
"Meat and Seafood",
"Pasta and Rice",
"Oils, Sauces, Salad Dressings, and Condiments",
"Cereals and Breakfast Foods",
"Soups and Canned Goods",
"Frozen Foods",
"Dairy, Cheese, and Eggs",
"Snacks and Crackers",
"Desserts",
"Beverages",
"Ice Cream",
"Fast foods",
"Coffee"
]
}
}