Add function for get sid

[wsdjeg]

PR Prelude

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• I have read and understood SpaceVim's CONTRIBUTING document.
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Why this change is necessary and useful?

[Please explain in detail why the changes in this PR are needed.]

[codecov]

Codecov Report

Merging #2350 into master will decrease coverage by 0.02%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master    #2350      +/-   ##
==========================================
- Coverage   25.57%   25.55%   -0.03%     
==========================================
  Files         277      277              
  Lines       14014    14026      +12     
==========================================
  Hits         3584     3584              
- Misses      10430    10442      +12