[Refactor] Replace if '_base_' with read_base()

[fangyixiao18]

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Codecov Report

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Additional details and impacted files

@@             Coverage Diff             @@
##             test-1.0    #1665   +/-   ##
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  Coverage            ?   65.51%           
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  Files               ?      329           
  Lines               ?    25587           
  Branches            ?     4077           
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  Hits                ?    16764           
  Misses              ?     8211           
  Partials            ?      612           

Flag	Coverage Δ
unittests	65.51% <0.00%> (?)

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