In dagster cloud serverless how is pex from s3 copied into ECS container?

In Dagster Cloud Serverless, when you deploy your code, it is packaged into a PEX (Python EXecutable) file, which is a self-contained Python environment that includes your code and all of its dependencies. This PEX file is then uploaded to an S3 bucket. When you run a pipeline in Dagster Cloud Serverless, an ECS task is triggered to execute the pipeline. The ECS container that runs the task is configured to pull the PEX file from the S3 bucket and execute it. The documentation does not provide explicit step-by-step details on how the PEX file is copied from S3 into the ECS container. However, typically in AWS ECS, you would use an ECS task definition to specify the location of your code (in this case, the PEX file in S3) and how it should be run. The task definition would include the necessary permissions for the ECS task to access the S3 bucket and retrieve the PEX file. If you need more detailed information on how this process is specifically handled within Dagster Cloud Serverless, I would recommend checking the Dagster Cloud documentation or reaching out to the Dagster community for guidance, as the provided documentation does not elaborate on the internal mechanics of this process.