Fix bug when getting search filters

[EricOuma]

Resolves # (issue)

Proposed changes

A None lookup was causing a KeyError. Fix is not proceeding if lookup is None.

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

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• I have read the CONTRIBUTING doc
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in downstream modules

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.10%. Comparing base (599ef24) to head (fc68f58).

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #82   +/-   ##
=======================================
  Coverage   77.10%   77.10%           
=======================================
  Files          12       12           
  Lines         594      594           
=======================================
  Hits          458      458           
  Misses        136      136           

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