Drupal get site wide email address?

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variable_get('site_mail', ini_get('sendmail_from'));

Looking into the system module, I found the settings form references the following:

variable_get('site_mail', ini_get('sendmail_from'));

In Drupal 8:

$site_mail = \Drupal::config('system.site')->get('mail');

$site_email = variable_get('site_mail', '');