func userFromOS(u *user.User) (User, error) {
	newUser := User{
		Name: u.Username,
		Home: u.HomeDir,
	}
	id, err := strconv.Atoi(u.Uid)
	if err != nil {
		return newUser, err
	}
	newUser.Uid = id
	id, err = strconv.Atoi(u.Gid)
	if err != nil {
		return newUser, err
	}
	newUser.Gid = id
	return newUser, nil
}
userFromOS converts an os/user.(*User) to local User

(This does not include Pass, Shell or Gecos)
package user
import (
	"bufio"
	"fmt"
	"io"
	"os"
	"os/user"
	"strconv"
	"strings"
)
const (
	minId = 0
	maxId = 1<<31 - 1  
)
var (
	ErrRange = fmt.Errorf("uids and gids must be in range %d-%d", minId, maxId)
)
type User struct {
	Name  string
	Pass  string
	Uid   int
	Gid   int
	Gecos string
	Home  string
	Shell string
}