Custom theme suggestions for container elements in drupal 8

THEMENAME_theme_suggestions_container_alter.php

<?php 

/**
 * Implements hook_theme_suggestions_alter() for container.
 */
function THEMENAME_theme_suggestions_container_alter(array &$suggestions, array &$variables)
{
  $name = '';
  $type = '';
  if (isset($variables['element']['#name'])) {
    $name = $variables['element']['#name'];
  }

  if (isset($variables['element']['#type'])) {
    $type = $variables['element']['#type'];
  }

  $suggestions[] = 'container__' . $type . '__' . $name;
}