const MultiChainGasPriceComparator = require('multichain-gas-price-comparator');
const comparator = new MultiChainGasPriceComparator([
'https://mainnet.infura.io/v3/YOUR-PROJECT-ID', // main
'https://ropsten.infura.io/v3/YOUR-PROJECT-ID', // Ropsten
'https://rinkeby.infura.io/v3/YOUR-PROJECT-ID', // Rinkeby
]);
comparator.getGasPrices().then(gasPrices => {
console.log(gasPrices);
});