UnusedUseFixer - code grooming
improve code coverage
minor #825 improve code coverage (keradus)

This PR was squashed before being merged into the 1.4-dev branch (closes #825).

Discussion
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improve code coverage

improve code coverage

Commits
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e01cc58 improve code coverage
minor #827 UnusedUseFixer - code grooming (keradus)

This PR was merged into the 1.4-dev branch.

Discussion
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UnusedUseFixer - code grooming

Commits
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2c83130 UnusedUseFixer - code grooming
UnusedUseFixer - add support for multiple NS