Expression Engine: Create multiple publish form tabs when installing a module - expressionengine

Question

Is it possible to create a module that outputs two tabs into the publish screen, or do I have two create another module to to create my second tab or just another tab.file.php file?
CODE
FILE: upd.my_module.php
class My_module_upd {
var $version = '1.0';
public function __construct(){
$this->EE =& get_instance();
}
public function install(){
$this->EE->load->dbforge();
$data = array(
'module_name' => 'My Module',
'module_version' => $this->version,
'has_cp_backend' => 'y',
'has_publish_fields' => 'y'
);
$this->EE->db->insert('modules', $data);
return true;
}
public function tabs(){
$tabs['tab_1'] = array(
'field_1' => array(
'visible' => TRUE,
'collapse' => FALSE,
'htmlbuttons' => TRUE,
'width' => '100%'
),
'field_2' => array(
'visible' => TRUE,
'collapse' => FALSE,
'htmlbuttons' => TRUE,
'width' => '100%'
)
);
$tabs['tab_2'] = array(
'field_1' => array(
'visible' => TRUE,
'collapse' => FALSE,
'htmlbuttons' => TRUE,
'width' => '100%'
),
);
return $tabs;
}
}
FILE: tab.my_module.php
class My_module_tab {
public function __construct(){
$this->EE =& get_instance();
}
public function publish_tabs($channel_id, $entry_id = ''){
$settings = array(
'field_1' => array(
'field_id' => 'field_1',
'field_label' => 'Field 1',
'field_type' => 'text',
'field_required' => 'n',
'field_data' => '',
'field_text_direction' => 'ltr',
'field_maxl' => 100,
'field_instructions' => '',
),
'field_2' => array(
'field_id' => 'field_2',
'field_label' => 'Field 2',
'field_type' => 'text',
'field_required' => 'n',
'field_data' => '',
'field_text_direction' => 'ltr',
'field_maxl' => 100,
'field_instructions' => '',
),
);
return $settings;
}
}
In the My_module_upd->tabs() method it looks like to can declare multiple tabs in the array but the My_module_tab class seems geared to controlling just one tab. Can anyone point me in the right direction?