docs: public static <T1, T2, R1, R2, R> CompletableFuture<R> forEach3(CompletableFuture<? extends T1> value1,
                                                                      Function<? super T1, ? extends CompletableFuture<R1>> value2,
                                                                      BiFunction<? super T1, ? super R1, ? extends CompletableFuture<R2>> value3,
                                                                      Function3<? super T1, ? super R1, ? super R2, ? extends R> yieldingFunction) {
  
          return value1.thenCompose(in -> {
  
              CompletableFuture<R1> a = value2.apply(in);
              return a.thenCompose(ina -> {
                  CompletableFuture<R2> b = value3.apply(in,ina);
  
  
                      return b.thenApply(in2 -> yieldingFunction.apply(in, ina, in2));
  
  
              });
  
          });
  
      }