fix: synth.py clean up for multiple version

[summer-ji-eng]

No description provided.

[codecov]

Codecov Report

Merging #431 into master will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #431   +/-   ##
=======================================
  Coverage   98.56%   98.56%           
=======================================
  Files           8        8           
  Lines       16068    16068           
  Branches      392      392           
=======================================
  Hits        15837    15837           
  Misses        225      225           
  Partials        6        6           

Impacted Files	Coverage Δ
src/index.ts	100.00% <100.00%> (ø)

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