Create a user account programmatically in Drupal 8

    Here an example for create a user account programmatically in Drupal 8

    $language = \Drupal::languageManager()->getCurrentLanguage()->getId();
    $user = \Drupal\user\Entity\User::create();

//Mandatory settings
    $user->setPassword('password');
    $user->enforceIsNew();
    $user->setEmail('email');
    $user->setUsername('user_name');//This username must be unique and accept only a-Z,0-9, - _ @ .

//Optional settings
    $user->set("init", 'email');
    $user->set("langcode", $language);
    $user->set("preferred_langcode", $language);
    $user->set("preferred_admin_langcode", $language);
    //$user->set("setting_name", 'setting_value');
    $user->activate();

//Save user
    $res = $user->save();

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