[RFR] various clean ups
minor #823 [RFR] various clean ups (cordoval)

This PR was squashed before being merged into the master branch (closes #823).

Discussion
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[RFR] various clean ups

- [x] fixing typos and typehinting checkroute method
- [x] remove unused use statements
- [x] make consistent test use statement without line break separation

Commits
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727f5b7 [RFR] various clean ups