hardhat.config.js

require("@nomiclabs/hardhat-waffle");

// This is a sample Hardhat task. To learn how to create your own go to
// https://hardhat.org/guides/create-task.html
task("accounts", "Prints the list of accounts", async (taskArgs, hre) => {
  const accounts = await hre.ethers.getSigners();

  for (const account of accounts) {
    console.log(account.address);
  }
});

// You need to export an object to set up your config
// Go to https://hardhat.org/config/ to learn more

/**
 * @type import('hardhat/config').HardhatUserConfig
 */
 module.exports = {
  solidity: "0.8.4",
  networks: {
    hardhat: {
      chainId: 1337
    },
    mumbai: {
      // url: "https://rpc-mumbai.matic.today",
      url: "https://polygon-mumbai.g.alchemy.com/v2/rJtsvK7HmqIDegPktCeviwFpWBjkX7GC",
      accounts: [process.env.pk]
    },
    // polygon: {
    //   url: "https://polygon-rpc.com/",
    //   accounts: [process.env.pk]
    // }
  }
};