// Moves the rigidbody upwards in world coordinates
constantForce.force = Vector3.up * 10;

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    void Example() {
        constantForce.force = Vector3.up * 10;
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    def Example():
        constantForce.force = (Vector3.up * 10)