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A while ago, we started to work on Generalize easy to copy uuid, secret key and secret URL logic but we could not finish it.

There's a pull request that implements most of the logic, but it's not 100% finished.

What you have to do:

1. read the issue description and understand what needs to be done, if in doubt, ask questions on github (ping mentors on chat to speed up responses)
2. pull the changes implemented in the pull request #41 by Noumbissi, keep his commits intact to preserve authorship
3. follow up on the review comments we left in the pull request
4. finish any missing point of the original issue, including documentation, tests (ensure test coverage does not decrease) and updating the other openwisp modules (linked in the issue description) so that they use the code we're introducing now (instead of their own implementation), open 1 pull request for each module mentioned