https://api.drupal.org/api/drupal/core%21modules%21block%21tests%21modules%21block_test%21src%21Plugin%21Block%21TestCacheBlock.php/8.9.x
TestCacheBlock.php | Drupal API
phpdrupalapi
https://api.drupal.org/api/drupal/core%21modules%21block%21tests%21modules%21block_test%21src%21Plugin%21Block%21TestCacheBlock.php/function/TestCacheBlock%3A%3AgetCacheMaxAge/10
function TestCacheBlock::getCacheMaxAge | Drupal API
functiondrupalapi