replace __str__ by __repr__

[amueller]

Closes #739, #75

cc @Neeratyoy, @mfeurer

[amueller]

test failure in test_list_datasets_with_high_size_parameter seems unrelated?

[mfeurer]

test failure in test_list_datasets_with_high_size_parameter seems unrelated?

yep, it is. This one might fail sporadically if we concurrently delete stuff from the test server.

[Neeratyoy]

Thanks a lot, @amueller.

[mfeurer]

Thanks for your suggestion @amueller and the PR

However, it turns out that this now makes a unit test fail on Windows. Would you mind updating the test REGEX to accomodate for the change from __str__ to __repr__?

[codecov-io]

Codecov Report

Merging #743 into develop will increase coverage by 0.08%.
The diff coverage is 87.5%.

@@             Coverage Diff             @@
##           develop     #743      +/-   ##
===========================================
+ Coverage    87.89%   87.98%   +0.08%     
===========================================
  Files           36       36              
  Lines         4033     4077      +44     
===========================================
+ Hits          3545     3587      +42     
- Misses         488      490       +2

Impacted Files	Coverage Δ
openml/datasets/data_feature.py	70% <100%> (ø)	⬆️
openml/flows/flow.py	93.8% <100%> (ø)	⬆️
openml/evaluations/evaluation.py	61.53% <100%> (ø)	⬆️
openml/datasets/dataset.py	84.07% <100%> (ø)	⬆️
openml/exceptions.py	93.75% <100%> (-3.13%)	⬇️
openml/tasks/task.py	81.01% <100%> (ø)	⬆️
openml/setups/setup.py	42.3% <100%> (ø)	⬆️
openml/runs/run.py	85.71% <100%> (ø)	⬆️
openml/runs/trace.py	90.75% <100%> (ø)	⬆️
openml/study/study.py	64.36% <60%> (ø)	⬆️
... and 4 more

---

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[amueller]

Do you have an idea of why this fails on windows? That should be working, right?

[mfeurer]

Nope, maybe @PGijsbers knows. He (together with @WilliamRaynaut) set up the Windows tests and had some regex issues back then, too.

[PGijsbers]

I'm not sure. I tried the tests locally and they work on my Windows machine.

[amueller]

I might have gotten it.

[amueller]

hm still fails on linux on 3.5 :-/

[PGijsbers]

I might have gotten it.

I saw you were working on fixing it, so I checked against older versions too. All commits in this PR left me with passing unit tests (at least those that FAILED on Appveyor when I was pinged).

[amueller]

failures seem unrelated now.

[amueller]

yay thank you!