package main

import "fmt"

func main() {	
	slice := make([]int, 159)

	// Split the slice into batches of 20 items.
	batch := 20

	for i := 0; i < len(slice); i += batch {
		j := i + batch
		if j > len(slice) {
			j = len(slice)
		}
		fmt.Println(slice[i:j]) // Process the batch.
	}
	
	// Try it at https://play.golang.org/p/mgd814w8xx6
}