My childish attempts at creating a custom line-type

dsdm_membership_line_item.module

<?php
/**
 * @file  dsdm_membership_line_item.module
 * Defines the line-item-type for the DSDM Memberships
 *
 */


/**
 * This function simply returns information about the example to help the
 * user understand its purpose.
 */
function dsdm_membership_line_item_info_page() {
  return array(
    '#markup' => t('The line item example demonstrates adding a custom line item and also how to use related API functions. With this module enabled, an additional line item may be selected by add-to-cart forms.'),
  );
}

/**
 * Implements hook_commerce_line_item_type_info().
 *
 *
 * @see hook_commerce_line_item_type_info().
 * @see http://www.drupalcommerce.org/specification/info-hooks/checkout
 *
 */
function dsdm_membership_line_item_commerce_line_item_type_info() {

  $line_item_types['dsdm_membership_line_item'] = array(
    'name' => t('TEST membership_line_item 1'),
    'description' => t('Some Thing here'),
    'product' => TRUE,

    // Here you can change the text in the submit button in the order admin form.
    'add_form_submit_value' => t('Add DSDM Membership'),

    // 'base' basically provides magic naming for a set of callbacks
    // including the settings_form, checkout_form, etc. Here we'll use the
    // forms and callbacks provided for Commerce Product Reference module for
    // its product line item, so we'll use
    // commerce_product_line_item_configuration()
    // and commerce_product_line_item_title(), etc.
    // See example_line_item_2 for explicit callbacks.
    'base' => 'commerce_product_line_item',
  
	  'callbacks' => array(
	    'configuration' => 'dsdm_membership_line_item_commerce_product_line_item_configuration',
		),
	);

  return $line_item_types;
}


/**
 * Configure the line item with additional fields or whatever.
 *
 * This function is called by the line item module when it is enabled or this
 * module is enabled. It invokes this function using the configuration_callback
 * as specified above. Other modules defining product line item types should
 * use this function to ensure their types have the required fields.
 *
 * @param $line_item_type
 *   The info array of the line item type being configured.
 *
 * @see commerce_product_line_item_configuration()
 */
function dsdm_membership_line_item_commerce_product_line_item_configuration($line_item_type) {
  $type = $line_item_type['type'];

  // Here we could add fields or other configuration.
  


	 
}