hook_install

gistfile1.php

<?php
/**
 * Implements hook_install().
 */
function complex_widget_install() {
  // Create the content type using node_content as the base.
  $t = get_t();
  $node_type = array(
    'type' => 'my_node_type',
    'name' => $t('Complex widget example'),
    'base' => 'node_content',
    'description' => $t('A simple node that illustrates a complex field and widget'),
  );
  // Set content type defaults and save the new content type.
  $content_type = node_type_set_defaults($node_type);
  node_type_save($content_type);

  // Create all the fields we are adding to our content type.
  // http://api.drupal.org/api/function/field_create_field/7
  foreach (_complex_widget_installed_fields() as $field) {
    field_create_field($field);
  }

  // Create all the instances for our fields.
  // http://api.drupal.org/api/function/field_create_instance/7
  foreach (_complex_widget_installed_instances() as $instance) {
    $instance['entity_type'] = 'node';
    $instance['bundle'] = $node_type['type'];
    field_create_instance($instance);
  }
}