Why am I getting "404" instead of "200"?

// Problem: We need a simple way to look at a user's badge count and JavaScript points
// Solution: Use Node.js to connect to Treehouse's API to get profile information to print out

//Require https module
const https = require('https');
const username = "chalkers";

// Function to print message to console
function printMessage(username, badgeCount, points) {
    const message = '${username} has ${badgeCount} total badge(s) and ${points} points in JavaScript';
    console.log(message);
}

// Connect to the API URL (https://teamtreehouse.com/username.json)
const request = https.get('https://teamtreehouse.com/${username}.json', response => {

                        console.log(response.statusCode);
                        // Read the data
                        // Parse the data
                         //Print the data

                        });