Depends on what you mean with "deployment". Exposing a deep learning inference engine is easy, there is no magic regardless of which language one uses. Developing and training useful models and presenting them to end users in ways users are willing to pay money for takes thousands of lines of code, PhDs, senior developers with many years of experience. It's kind of naive to suggest that deployment of one api is easy. Yes it is but it's also just one of dozens of apis and considerations in the entire product development, testing, and deployment, and monetization process.
Depends on the application. I write PySpark pipelines for big data all the time and deploy models in 50 lines of code or less. You don't have to write much code for model deployment any more, as much of the work has been subsumed by high-level ML APIs or products such as DataRobot.
https://developers.google.com/machine-learning/guides/rules-of-ml/
Regards,
PTR
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