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[tsmbland]

Description

Please include a summary of the change and which issue is fixed (if any). Please also
include relevant motivation and context. List any dependencies that are required for
this change.

Fixes # (issue)

Type of change

• Bug fix (non-breaking change to fix an issue)
• New feature (non-breaking change to add functionality)
• Refactoring (non-breaking, non-functional change to improve maintainability)
• Optimization (non-breaking change to speed up the code)
• Breaking change (whatever its nature)
• Documentation (improve or add documentation)

Key checklist

• All tests pass: $ cargo test
• The documentation builds and looks OK: $ cargo doc
• Update release notes for the latest release if this PR adds a new feature or fixes a bug
  present in the previous release

Further checks

• Code is commented, particularly in hard-to-understand areas
• Tests added that prove fix is effective or that feature works

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.03%. Comparing base (9dddcbb) to head (d6a9e5e).

Additional details and impacted files

@@                 Coverage Diff                  @@
##           lexico_optimisation    #1471   +/-   ##
====================================================
  Coverage                90.03%   90.03%           
====================================================
  Files                       60       60           
  Lines                     8631     8631           
  Branches                  8631     8631           
====================================================
  Hits                      7771     7771           
  Misses                     541      541           
  Partials                   319      319           

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