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# What’s new in 1.3.3 (September 12, 2021)

These are the changes in pandas 1.3.3. See Release notes for a full changelog including other versions of pandas.

## Fixed regressions

- Fixed regression in `DataFrame` constructor failing to broadcast for defined `Index` and len one list of `Timestamp` (GH 42810)

- Fixed regression in `DataFrameGroupBy.agg()` and `SeriesGroupBy.agg()` incorrectly raising in some cases (GH 42390)

- Fixed regression in `DataFrameGroupBy.apply()` and `SeriesGroupBy.apply()` where `nan` values were dropped even with `dropna=False` (GH 43205)

- Fixed regression in `DataFrameGroupBy.quantile()` and `SeriesGroupBy.quantile()` which were failing with `pandas.NA` (GH 42849)

- Fixed regression in `merge()` where `on` columns with `ExtensionDtype` or `bool` data types were cast to `object` in `right` and `outer` merge (GH 40073)

- Fixed regression in `RangeIndex.where()` and `RangeIndex.putmask()` raising `AssertionError` when result did not represent a `RangeIndex` (GH 43240)

- Fixed regression in `read_parquet()` where the `fastparquet` engine would not work properly with fastparquet 0.7.0 (GH 43075)

- Fixed regression in `DataFrame.loc.__setitem__()` raising `ValueError` when setting array as cell value (GH 43422)

- Fixed regression in `is_list_like()` where objects with `__iter__` set to `None` would be identified as iterable (GH 43373)

- Fixed regression in `DataFrame.__getitem__()` raising error for slice of `DatetimeIndex` when index is non monotonic (GH 43223)

- Fixed regression in `Resampler.aggregate()` when used after column selection would raise if `func` is a list of aggregation functions (GH 42905)

- Fixed regression in `DataFrame.corr()` where Kendall correlation would produce incorrect results for columns with repeated values (GH 43401)

- Fixed regression in `DataFrame.groupby()` where aggregation on columns with object types dropped results on those columns (GH 42395, GH 43108)

- Fixed regression in `Series.fillna()` raising `TypeError` when filling `float` `Series` with list-like fill value having a dtype which couldn’t cast lostlessly (like `float32` filled with `float64`) (GH 43424)

- Fixed regression in `read_csv()` raising `AttributeError` when the file handle is an `tempfile.SpooledTemporaryFile` object (GH 43439)

- Fixed performance regression in `core.window.ewm.ExponentialMovingWindow.mean()` (GH 42333)

## Performance improvements

- Performance improvement for `DataFrame.__setitem__()` when the key or value is not a `DataFrame`, or key is not list-like (GH 43274)

## Bug fixes

- Fixed bug in `DataFrameGroupBy.agg()` and `DataFrameGroupBy.transform()` with `engine="numba"` where `index` data was not being correctly passed into `func` (GH 43133)

## Contributors

A total of 18 people contributed patches to this release. People with a “+” by their names contributed a patch for the first time.

- Ali McMaster

- Irv Lustig

- Matthew Roeschke

- Matthew Zeitlin

- MeeseeksMachine

- Pandas Development Team

- Patrick Hoefler

- Prerana Chakraborty +

- Richard Shadrach

- Shoham Debnath

- Simon Hawkins

- Thomas Li

- Torsten Wörtwein

- Zach Rait +

- aiudirog +

- attack68

- jbrockmendel

- suoniq +