You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: cpuset.go
    path of file: ./repos/kubeedge/vendor/github.com/opencontainers/runc/libcontainer/cgroups/systemd
    
    the code of the file until where you have to start completion: package systemd

import (
	"errors"
	"math/big"
	"strconv"
	"strings"
)

// RangeToBits converts a text representation of a CPU mask (as written to
// or read from cgroups' cpuset.* files, e.g. "1,3-5") to a slice of bytes
// with the corresponding bits set (as consumed by systemd over dbus as
// AllowedCPUs/AllowedMemoryNodes unit property value).
func RangeToBits(str string) ([]byte, error) {
	bits := new(big.Int)

	for _, r := range strings.Split(str, ",") {
		// allow extra spaces around
		r = strings.TrimSpace(r)
		// allow empty elements (extra commas)
		if r == "" {
			continue
		}
		ranges := strings.SplitN(r, "-", 2)
		if len(ranges) > 1 {
			start, err := strconv.ParseUint(ranges[0], 10, 32)
			if err != nil {
				return nil, err

    
func RangeToBits(str string) ([]byte, error) {
	bits := new(big.Int)

	for _, r := range strings.Split(str, ",") {
		// allow extra spaces around
		r = strings.TrimSpace(r)
		// allow empty elements (extra commas)
		if r == "" {
			continue
		}
		ranges := strings.SplitN(r, "-", 2)
		if len(ranges) > 1 {
			start, err := strconv.ParseUint(ranges[0], 10, 32)
			if err != nil {
				return nil, err
			}
			end, err := strconv.ParseUint(ranges[1], 10, 32)
			if err != nil {
				return nil, err
			}
			if start > end {
				return nil, errors.New("invalid range: " + r)
			}
			for i := start; i <= end; i++ {
				bits.SetBit(bits, int(i), 1)
			}
		} else {
			val, err := strconv.ParseUint(ranges[0], 10, 32)
			if err != nil {
				return nil, err
			}
			bits.SetBit(bits, int(val), 1)
		}
	}

	ret := bits.Bytes()
	if len(ret) == 0 {
		// do not allow empty values
		return nil, errors.New("empty value")
	}

	// fit cpuset parsing order in systemd
	for l, r := 0, len(ret)-1; l < r; l, r = l+1, r-1 {
		ret[l], ret[r] = ret[r], ret[l]
	}
	return ret, nil
}