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# What’s new in 1.3.5 (December 12, 2021)

These are the changes in pandas 1.3.5. See Release notes for a full changelog including other versions of pandas.

## Fixed regressions

- Fixed regression in `Series.equals()` when comparing floats with dtype object to None (GH 44190)

- Fixed regression in `merge_asof()` raising error when array was supplied as join key (GH 42844)

- Fixed regression when resampling `DataFrame` with `DateTimeIndex` with empty groups and `uint8`, `uint16` or `uint32` columns incorrectly raising `RuntimeError` (GH 43329)

- Fixed regression in creating a `DataFrame` from a timezone-aware `Timestamp` scalar near a Daylight Savings Time transition (GH 42505)

- Fixed performance regression in `read_csv()` (GH 44106)

- Fixed regression in `Series.duplicated()` and `Series.drop_duplicates()` when Series has `Categorical` dtype with boolean categories (GH 44351)

- Fixed regression in `DataFrameGroupBy.sum()` and `SeriesGroupBy.sum()` with `timedelta64[ns]` dtype containing `NaT` failing to treat that value as NA (GH 42659)

- Fixed regression in `RollingGroupby.cov()` and `RollingGroupby.corr()` when `other` had the same shape as each group would incorrectly return superfluous groups in the result (GH 42915)

## Contributors

A total of 10 people contributed patches to this release. People with a “+” by their names contributed a patch for the first time.

- Ali McMaster

- Matthew Roeschke

- Matthew Zeitlin

- MeeseeksMachine

- Pandas Development Team

- Patrick Hoefler

- Simon Hawkins

- Thomas Li

- Tobias Pitters

- jbrockmendel