You can create server using dart language. You can use API of any Language like ( Node. js, Python, Java, PHP) as a backend and use flutter just to fetch the data . It is most effective approach for large applications!
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On the other hand flutter is the SDK( software development kit) that uses dart as the language. So flutter is limited to the development of application and it is meant for that only but python is the programming language that is being used in machine learning,backends , automation and many more things .21 Ara 2018
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