BUG: Fix lxml import in show_versions

[nixphix]

Fixed lxml import issue

• closes show_versions fails on master with latest lxml #23934
• tests added / passed
• passes git diff upstream/master -u -- "*.py" | flake8 --diff

[pep8speaks]

Hello @nixphix! Thanks for submitting the PR.

• There are no PEP8 issues in the file pandas/util/_print_versions.py !

[jreback]

can you add a test for this?

somethign like

subprocess.check_call([sys.executable, "-c", "import pandas; pandas.show_versions()"])

would be enough

[codecov]

Codecov Report

Merging #23949 into master will increase coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #23949      +/-   ##
==========================================
+ Coverage   92.31%   92.31%   +<.01%     
==========================================
  Files         161      161              
  Lines       51473    51513      +40     
==========================================
+ Hits        47517    47554      +37     
- Misses       3956     3959       +3

Flag	Coverage Δ
#multiple	90.71% <ø> (ø)	⬆️
#single	42.42% <ø> (-0.02%)	⬇️

Impacted Files	Coverage Δ
pandas/util/_print_versions.py	15.71% <ø> (ø)	⬆️
pandas/core/arrays/timedeltas.py	96.25% <0%> (-0.19%)	⬇️
pandas/tseries/offsets.py	96.84% <0%> (-0.14%)	⬇️
pandas/core/groupby/ops.py	96.75% <0%> (-0.05%)	⬇️
pandas/core/indexes/interval.py	94.69% <0%> (ø)	⬆️
pandas/core/indexes/multi.py	95.49% <0%> (ø)	⬆️
pandas/core/frame.py	97.02% <0%> (ø)	⬆️
pandas/core/generic.py	96.84% <0%> (ø)	⬆️
pandas/core/indexes/period.py	93.07% <0%> (ø)	⬆️
pandas/core/indexes/base.py	96.48% <0%> (ø)	⬆️
... and 9 more

---

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[nixphix]

@jreback Added test case

[jreback]

hmm then why didn’t our build fail?

[TomAugspurger]

Possibly we didn't have an environment with lxml but not openpyxl.

…

On Wed, Nov 28, 2018 at 12:14 PM Jeff Reback ***@***.***> wrote: hmm then why didn’t our build fail? — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#23949 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABQHIrsdFKOtG5nQjQvMduBoAw_wJfTEks5uztJqgaJpZM4Y2AZF> .

[TomAugspurger]

Thanks @nixphix!