docs: @Nullable
      public static NetworkParameters fromID(String id) {
          if (id.equals(ID_MAINNET)) {
              return MainNetParams.get();
          } else if (id.equals(ID_TESTNET)) {
              return TestNet3Params.get();
          } else if (id.equals(ID_UNITTESTNET)) {
              return UnitTestParams.get();
          } else if (id.equals(ID_REGTEST)) {
              return RegTestParams.get();
          } else {
              return null;
          }
      }