A company needs to run a critical Python data processing job each night.

The job runs for about 1 hour and must not be interrupted, so Lambda is not suitable because AWS Lambda has a maximum execution time of 15 minutes. Fargate Spot is also not appropriate because the workload explicitly cannot tolerate interruption. The most cost-effective remaining design is to run the Python script on an EC2 On-Demand instance only during the nightly processing window and automate instance start/stop around the schedule. That avoids paying for compute all day while preserving uninterrupted execution during the job. The Step Functions Express option is not the natural fit for a single long-running Python job of this type. Therefore, an EC2 instance scheduled to run only when needed is the most economical answer among the choices.

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