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## Summary
Fix `E231` bug: Inconsistent catch compared to pycodestyle, such as when
dict nested in list. Resolves#10113.
## Test Plan
Example from #10113 added to test fixture.
## Summary
We were considering the `{` within an f-string to be a left brace, which
caused the "space-after-colon" rule to trigger incorrectly.
Closes https://github.com/astral-sh/ruff/issues/8299.