I was a bit quick to approve. The lgtm ci still fails with

[build-stderr] ImportError: Your installation of numpy 1.16.3 is out-of-date.
[build-stderr] scikit-learn requires numpy >= 1.17.3.

I was a bit quick to approve. The lgtm ci still fails with

[build-stderr] ImportError: Your installation of numpy 1.16.3 is out-of-date.
[build-stderr] scikit-learn requires numpy >= 1.17.3.

I was also curious about that. I think that the one failing is from commit effdd6e of the main branch: https://lgtm.com/projects/g/scikit-learn/scikit-learn/logs/rev/pr-ad65350510e627f1dcd72af957303fbd0cf51341/lang:cpp/stage:Build%20main_effdd6e215c67f2ae8ed1e378ea1661e936059a4

In fact, the merge commit is building successfully: https://lgtm.com/projects/g/scikit-learn/scikit-learn/logs/rev/pr-ad65350510e627f1dcd72af957303fbd0cf51341/lang:cpp/stage:Build%20merge_8045c630e255e43accbbeb1a690608d120ca8f44.

I wonder if we should turn off the C/C++ one, we have not gotten much results from it:

https://lgtm.com/projects/g/scikit-learn/scikit-learn/alerts/?mode=list&lang=cpp

https://lgtm.com/projects/g/scikit-learn/scikit-learn/history/

The status report for lgtm is showing the error from main, specifically this commit: effdd6e

I think this PR is good for merging.