DOC: df.astype example using dictionary

[stevennic]

Closes #26990

[codecov]

Codecov Report

Merging #26994 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #26994      +/-   ##
==========================================
- Coverage   91.99%   91.98%   -0.01%     
==========================================
  Files         180      180              
  Lines       50774    50774              
==========================================
- Hits        46711    46707       -4     
- Misses       4063     4067       +4

Flag	Coverage Δ
#multiple	90.63% <ø> (ø)	⬆️
#single	41.83% <ø> (-0.09%)	⬇️

Impacted Files	Coverage Δ
pandas/core/generic.py	94.2% <ø> (ø)	⬆️
pandas/io/gbq.py	88.88% <0%> (-11.12%)	⬇️
pandas/core/frame.py	96.89% <0%> (-0.12%)	⬇️

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[codecov]

Codecov Report

Merging #26994 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #26994      +/-   ##
==========================================
- Coverage   91.99%   91.98%   -0.01%     
==========================================
  Files         180      180              
  Lines       50774    50774              
==========================================
- Hits        46711    46707       -4     
- Misses       4063     4067       +4

Flag	Coverage Δ
#multiple	90.63% <ø> (ø)	⬆️
#single	41.83% <ø> (-0.09%)	⬇️

Impacted Files	Coverage Δ
pandas/core/generic.py	94.2% <ø> (ø)	⬆️
pandas/io/gbq.py	88.88% <0%> (-11.12%)	⬇️
pandas/core/frame.py	96.89% <0%> (-0.12%)	⬇️

---

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 a14874f...c2d1702. Read the comment docs.

[WillAyd]

Thanks! I think this looks good though caused some CI failures if you can take a look.

@datapythonista in case you have any input

[stevennic]

Yea the errors don't seem to be related to my changes:
Worker 'gw0' crashed while running 'pandas/tests/test_sorting.py::TestSafeSort::test_labels_out_of_bound[-1]'

[WillAyd]

Restarted to be sure but I agree probably unrelated so lgtm. @datapythonista @TomAugspurger if either of you want to take a look feel free to merge

[TomAugspurger]

Thanks!