code: public static <T, U, R, E extends Throwable> @NonNull BiFunction<T, U, R> rethrowBiFunction(final @NonNull ThrowingBiFunction<T, U, R, E> function) {
      return function;
    }
docs: Returns the same throwing bi-function.
  
  @param function the bi-function
  @param <T> the first input type
  @param <U> the second input type
  @param <R> the output type
  @param <E> the exception type
  @return the bi-function