code: public static <V1, V2> HMap hMap(TypeSafeKey<?, V1> key1, V1 value1,
                                       TypeSafeKey<?, V2> key2, V2 value2) {
          return singletonHMap(key1, value1).put(key2, value2);
      }
docs: Static factory method for creating an HMap from two given associations.
  
  @param key1   the first mapped key
  @param value1 the value mapped at key1
  @param key2   the second mapped key
  @param value2 the value mapped at key2
  @param <V1>   value1's type
  @param <V2>   value2's type
  @return an HMap with the given associations