Don't use bare except when importing

[Ed Singleton (Singletoned)]

Using a bare except statement when importing hides other errors, which then get lost when the next import fails.

[Ray Luo (rayluo)]

Thanks for your suggestion. We could have been written in the way that you proposed. Out of curiosity, under what scenario did you run into that import raising non-ImportError?

Besides, the current implementation dates back to Python 2.7 era, and we will probably remove the entire try...except... in the foreseeable future, making this pattern irrelevant.

[Ed Singleton (Singletoned)]

I don't actually know what caused the non-ImportError. It was a one off occurrence in our logs, and the true error was disguised by the bare except, hence the PR. I'd be grateful if this could be fixed, so that if it happens again, we'll have the correct traceback in our logs.

I strongly recommend never using a bare try...except... at all, and in fact most linters will automatically pick this up and mark it as an error.

Note that you are using a better pattern just a few lines below the change in this PR.

A better pattern overall is to not use try at all, and to explicitly test for a version of Python and modify the behaviour according to that (which is what you are doing in other places in the code).

[Ray Luo (rayluo)]

Thanks for the report.

If you would also like to add more commits into this PR to change other bare except, we will happily take it. Or we can also accept this PR as-is.

[Ed Singleton (Singletoned)]

Thanks! I'll do the others in other PRs, as and when I come across them