new EntryTransformer<Number, Number, Double>() {
          @Override
          public Double transformEntry(Number key, Number value) {
            return key.doubleValue() + value.doubleValue();
          }
        };

    Map<Object, Double> objectKeyed;
    Map<Number, Double> numberKeyed;
    Map<Integer, Double> integerKeyed;

        new EntryTransformer<Number, Number, Double>() {
          @Override
          public Double transformEntry(Number key, Number value) {
            return key.doubleValue() + value.doubleValue();
          }
        };

    Map<Object, Double> objectKeyed;
    Map<Number, Double> numberKeyed;
    Map<Integer, Double> integerKeyed;

                }
            } else if (doubleFieldSet.contains(key)) {
                if (value instanceof final Number num) {
                    value = num.doubleValue();
                } else {
                    value = DfTypeUtil.toDouble(value.toString());
                }
            }
            return new Pair<>(key, value);