Fix circular import loop

[mr-c]

Motivation

While testing the python3-smart-open package in Debian, I ran into a circular import error.

Tests

If you're fixing a bug, consider test-driven development:

1. Create a unit test that demonstrates the bug. The test should fail.
2. Implement your bug fix.
3. The test you created should now pass.

If you're implementing a new feature, include unit tests for it.

Make sure all existing unit tests pass.
You can run them locally using:

pytest smart_open

If there are any failures, please fix them before creating the PR (or mark it as WIP, see below).

Work in progress

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We'll skip reviewing it for the time being.
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Checklist

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• Picked a concise, informative and complete title
• Clearly explained the motivation behind the PR
• Linked to any existing issues that your PR will be solving
• Included tests for any new functionality
• Checked that all unit tests pass

Workflow

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Rebasing can make your commits look a bit cleaner, but it also makes life more difficult from the reviewer, because they are no longer able to distinguish between code that has already been reviewed, and unreviewed code.

[mpenkov]

Can you please show the error you encountered? It's not being picked up by any of our tests.

[mr-c]

Weird, now I can't reproduce it :-( Sorry!