TST: changed behavior of df.loc on multiindex

[gamenerd457]

-added unittest for issue #43599
-error occurs due to different versions of pandas
-made the requested changes

[pep8speaks]

Hello @gamenerd457! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file pandas/tests/indexing/multiindex/test_loc.py:

Line 915:1: E302 expected 2 blank lines, found 0
Line 916:5: E265 block comment should start with '# '
Line 918:14: E251 unexpected spaces around keyword / parameter equals
Line 918:16: E251 unexpected spaces around keyword / parameter equals
Line 918:87: E251 unexpected spaces around keyword / parameter equals
Line 918:89: E251 unexpected spaces around keyword / parameter equals
Line 918:89: E501 line too long (96 > 88 characters)
Line 919:9: E123 closing bracket does not match indentation of opening bracket's line
Line 920:28: E231 missing whitespace after ','
Line 920:32: E231 missing whitespace after ','
Line 922:14: E251 unexpected spaces around keyword / parameter equals
Line 922:16: E251 unexpected spaces around keyword / parameter equals
Line 922:86: E251 unexpected spaces around keyword / parameter equals
Line 922:88: E251 unexpected spaces around keyword / parameter equals
Line 922:89: E501 line too long (95 > 88 characters)
Line 923:9: E123 closing bracket does not match indentation of opening bracket's line

Comment last updated at 2021-10-11 13:43:30 UTC

[phofl]

Please finish #43879