How to upload a file to the server through the site?

Question

Flask

Essence of the question:
There is a page with a file selection button and a "send" button on it.
What is the easiest way to organize file upload to the server? The implementation language doesn't really matter.

(I apologize in advance for such a question, I have not dealt with backend before). I will be very grateful!

Answer 1

On the git, I found a ready-made version in Flask. Maybe someone will be useful.
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