Assorted cleanups

[jbrockmendel]

• closes #xxxx
• tests added / passed
• passes git diff upstream/master -u -- "*.py" | flake8 --diff
• whatsnew entry

[codecov]

Codecov Report

Merging #26975 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master   #26975      +/-   ##
==========================================
+ Coverage   91.87%   91.88%   +<.01%     
==========================================
  Files         180      180              
  Lines       50746    50735      -11     
==========================================
- Hits        46623    46617       -6     
+ Misses       4123     4118       -5

Flag	Coverage Δ
#multiple	90.47% <100%> (+0.01%)	⬆️
#single	41.12% <0%> (-0.07%)	⬇️

Impacted Files	Coverage Δ
pandas/core/internals/managers.py	96% <ø> (+0.78%)	⬆️
pandas/io/formats/format.py	97.91% <100%> (ø)	⬆️
pandas/io/gbq.py	88.88% <0%> (-11.12%)	⬇️
pandas/core/frame.py	96.89% <0%> (-0.12%)	⬇️
pandas/util/testing.py	90.94% <0%> (+0.1%)	⬆️

---

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Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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[codecov]

Codecov Report

Merging #26975 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master   #26975      +/-   ##
==========================================
+ Coverage   91.87%   91.88%   +<.01%     
==========================================
  Files         180      180              
  Lines       50746    50735      -11     
==========================================
- Hits        46623    46617       -6     
+ Misses       4123     4118       -5

Flag	Coverage Δ
#multiple	90.47% <100%> (+0.01%)	⬆️
#single	41.12% <0%> (-0.07%)	⬇️

Impacted Files	Coverage Δ
pandas/core/internals/managers.py	96% <ø> (+0.78%)	⬆️
pandas/io/formats/format.py	97.91% <100%> (ø)	⬆️
pandas/io/gbq.py	88.88% <0%> (-11.12%)	⬇️
pandas/core/frame.py	96.89% <0%> (-0.12%)	⬇️
pandas/util/testing.py	90.94% <0%> (+0.1%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update cfd65e9...7f74905. Read the comment docs.

[codecov]

Codecov Report

Merging #26975 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master   #26975      +/-   ##
==========================================
+ Coverage   91.87%   91.88%   +<.01%     
==========================================
  Files         180      180              
  Lines       50746    50735      -11     
==========================================
- Hits        46623    46617       -6     
+ Misses       4123     4118       -5

Flag	Coverage Δ
#multiple	90.47% <100%> (+0.01%)	⬆️
#single	41.12% <0%> (-0.07%)	⬇️

Impacted Files	Coverage Δ
pandas/core/internals/managers.py	96% <ø> (+0.78%)	⬆️
pandas/io/formats/format.py	97.91% <100%> (ø)	⬆️
pandas/io/gbq.py	88.88% <0%> (-11.12%)	⬇️
pandas/core/frame.py	96.89% <0%> (-0.12%)	⬇️
pandas/util/testing.py	90.94% <0%> (+0.1%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update cfd65e9...7f74905. Read the comment docs.

[jreback]

thanks @jbrockmendel