Symfony DIC - 重新初始化实例

I am using Symfony DIC using yaml file for example

services:
    mailer:
        class:     Mailer
        arguments: ['%mailer.transport%']
    newsletter_manager:
        class:     NewsletterManager
        calls:
            - [setMailer, ['@mailer']]

And then i am fetching the object by using

->getContainer()
->get('newsletter_manager');

How can i create a new instance of the object each time i am getting it? I want to reinitialize it for every use.

Thanks

From symfony docs:

In order to always get a new instance, set the shared setting to false in your service definition:

services:
    AppBundle\SomeNonSharedService:
        shared: false