ref: run_pretrain_routine -> setup_training

[williamFalcon]

What does this PR do?

Fixes # (issue)

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[codecov]

Codecov Report

Merging #3294 into master will increase coverage by 3%.
The diff coverage is 46%.

@@           Coverage Diff           @@
##           master   #3294    +/-   ##
=======================================
+ Coverage      86%     89%    +3%     
=======================================
  Files          88      88            
  Lines        8119    8328   +209     
=======================================
+ Hits         6955    7394   +439     
+ Misses       1164     934   -230