fix link to npy

[andremoeller]

Issue #, if available:

Description of changes:

Merge Checklist

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• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works (if appropriate)
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[codecov-io]

Codecov Report

Merging #202 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #202   +/-   ##
=======================================
  Coverage   91.03%   91.03%           
=======================================
  Files          42       42           
  Lines        2699     2699           
=======================================
  Hits         2457     2457           
  Misses        242      242

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