These contracts are used here
This project demonstrates a basic Hardhat use case. It comes with a sample contract, a test for that contract, a sample script that deploys that contract, and an example of a task implementation, which simply lists the available accounts.
Try running some of the following tasks:
npx hardhat accounts
npx hardhat compile
npx hardhat clean
npx hardhat test
npx hardhat node
node scripts/sample-script.js
npx hardhat help