Use of tableselect [SOLVED]

In this case the code (function) is an exact copy of the tutorial you linked to.

I now have installed a clean Drupal 7.22 site with only one custom mudule on it to test the Tutorial code and hopefully learn to understand the concept.
The module called tableselect have two files:
the tableselect.info and the tableselect.module file the code comes here:

<?php

 /**
 * Define the user permission.
 */
function tableselct_permission() {
  return array(
     'view tableselect' => array(
      'title' => t('Tableselect'),
      'description' => t('Tableselect.'),
    ),
   
  );
} 
 
/**
 * Implements hook_menu().
 */
function tableselect_menu() {
    $items['my_form'] = array(
    'title' => t('Select table example'),
    'description' => t('Select table tutorial'),
    'page callback' => 'my_form',
    'access callback' => 'user_access',
	'access arguments' => array('view tableselect'),
  );  
  return $items;
  }
// The tutorial function  
function my_form($form, $form_state)
{
  $users = array
  (
    array('uid' => 1, 'first_name' => 'Indy', 'last_name' => 'Jones'),
    array('uid' => 2, 'first_name' => 'Darth', 'last_name' => 'Vader'),
    array('uid' => 3, 'first_name' => 'Super', 'last_name' => 'Man'),
  );
 
  $header = array
  (
    'first_name' => t('First Name'),
    'last_name' => t('Last Name'),
  );
  $options = array();
  foreach($users as $user)
  {
    $options[$user['uid']] =array
    (
      'first_name' => $user['first_name'],
      'last_name' => $user['last_name'],
    );
  }
  $form['table'] = array
  (
    '#type' => 'tableselect',
    '#header' => $header,
    '#options' => $options,
    '#empty' => t('No users found'),
  );
  $form['submit'] = array
  (
    '#type' => 'submit',
    '#value' => t('Submit'),
  );
  return $form;
}

It produce an empty table an this this errormessage:

Warning: Missing argument 1 for my_form() in my_form() (line 30 of C:\xampp_old\htdocs\tableselect\sites\all\modules\tableselect\tableselect.module).
Warning: Missing argument 2 for my_form() in my_form() (line 30 of C:\xampp_old\htdocs\tableselect\sites\all\modules\tableselect\tableselect.module).

After a refresh it also generate this error:
Notice: Undefined index: #attributes in theme_tableselect() (line 3332 of C:\xampp_old\htdocs\tableselect\includes\form.inc).