Fix unused imports in lalinspiral python code
Description
This MR fixes a number of unused imports, and undefined names, as identifed by flake8. Some harmlessly unused imports were refactored to appease the linter (e.g. __date__ and __version__), I can't figure out a way to have the linter ignore a line based on a regex.
API Changes and Justification
Backwards Compatible Changes
- This change introduces no API changes
- This change adds new API calls
Backwards Incompatible Changes
- This change modifies an existing API
- This change removes an existing API
If any of the Backwards Incompatible check boxes are ticked please provide a justification why this change is necessary and why it needs to be done in a backwards incompatible way.
Review Status
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