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### Description
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Remove a redundant assignment in the engine creation file.
### Checklist
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This pull request is:
- [x] A documentation / typographical error fix
- Good to go, no issue or tests are needed
- [ ] A short code fix
- please include the issue number, and create an issue if none exists, which
must include a complete example of the issue. one line code fixes without an
issue and demonstration will not be accepted.
- Please include: `Fixes: #<issue number>` in the commit message
- please include tests. one line code fixes without tests will not be accepted.
- [ ] A new feature implementation
- please include the issue number, and create an issue if none exists, which must
include a complete example of how the feature would look.
- Please include: `Fixes: #<issue number>` in the commit message
- please include tests.
**Have a nice day!**
Closes: #4944
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/4944
Pull-request-sha:
4a0e6206f0ae5ff5350ecaa6f998bc3dc0c26cdd
Change-Id: Ie491b071e3392334947d3b8ba84c7323c1b15b6e