BUG: Fix inconsistency when read_csv reads MultiIndex with empty values (#59560) #62644
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allamlobna force-pushed the bugfix/clean-empty-vals-multiindex branch from 6a40ca3 to a399a8e Compare 
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read_csvreads MultiIndex with empty values #59560doc/source/whatsnew/vX.X.X.rstfile if fixing a bug or adding a new feature.Summary
This PR fixes an inconsistency where
read_csvreplaced emptyMultiIndex column level values with automatically generated
"Unnamed: x_level_y"placeholders.Empty values are now preserved as empty strings (
""),matching MultiIndex index behavior and ensuring consistent
roundtrip results between
to_csvandread_csv.Changes
_clean_column_levels()helper to normalize MultiIndexcolumn labels in
BaseParser._extract_multi_indexer_columns()to use it.test_multi_index_unnamed()expectations.test_header.py.Impact