feat: Set DefaultPairs with defaultable pairs

[JinnyYi]

ref: #704

[codecov]

Codecov Report

Merging #719 (1453353) into master (cd79fe7) will decrease coverage by 0.02%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master     #719      +/-   ##
==========================================
- Coverage   12.39%   12.36%   -0.03%     
==========================================
  Files          22       22              
  Lines        1485     1488       +3     
==========================================
  Hits          184      184              
- Misses       1294     1297       +3     
  Partials        7        7              

Flag	Coverage Δ
unittests	12.36% <0.00%> (-0.03%)	⬇️

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Impacted Files	Coverage Δ
tests/generated.go	2.24% <0.00%> (-0.02%)	⬇️

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