### Question:
MempoolFeeRateProvider extends FeeRateProvider { protected FeeRate doGet() { long estimatedFeeRate = MIN_FEE_RATE; try { estimatedFeeRate = getEstimatedFeeRate(); } catch (Exception e) { log.error("Error retrieving bitcoin mining fee estimation: " + e.getMessage()); } return new FeeRate("BTC", estimatedFeeRate, Instant.now().getEpochSecond()); } MempoolFeeRateProvider(Environment env);   }### Answer:
@Test public void doGet_successfulCall() { MempoolFeeRateProvider feeRateProvider = new MempoolFeeRateProvider.First(env); FeeRate retrievedFeeRate = feeRateProvider.doGet(); assertTrue(retrievedFeeRate.getPrice() >= FeeRateProvider.MIN_FEE_RATE); assertTrue(retrievedFeeRate.getPrice() <= FeeRateProvider.MAX_FEE_RATE); }