adding name of duplicate name to error message

[shimwell]

We have some scripts that add many names and would benefit from at slight tweaked error message. So when the error is triggered we know what the incorrect name is.

Would we be able to extend the error message like this

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.74%. Comparing base (0c0a661) to head (b35ec6e).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1893   +/-   ##
=======================================
  Coverage   95.74%   95.74%           
=======================================
  Files          29       29           
  Lines        7583     7583           
  Branches     1141     1141           
=======================================
  Hits         7260     7260           
  Misses        193      193           
  Partials      130      130           

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[adam-urbanczyk]

Simple change, merging after black fix.