Create a Lambda notification in an S3 bucket with CloudFormation
<p>I'm trying to create an S3 trigger for a Lambda function in a CloudFormation Template. The S3 bucket already exists, and the Lambda function is being created.</p>

<p><a href="https://serverfault.com/a/611069">This</a> says it's not possible to modify pre-existing infrastructure (S3 in this case) with a CFT, but <a href="https://stackoverflow.com/a/36339880/5182113">this</a> seems to say that the bucket has to be pre-existing.</p>

<ol>
<li><p>It seems that the trigger can't be created using a CFT type "AWS::Lambda..." and that the source service needs to create the trigger. In my case, that's a NotificationConfiguration-LambdaConfiguration for an s3 bucket. Is all of that correct?</p></li>
<li><p>When I try to add a NotificationConfiguration to an existing S3 bucket with a CFT, it says that I can't. Is there any way to do this?</p></li>
</ol>