From 4d5b0f9c59cedbc96405d579105f06c8db578539 Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 14:52:17 +0100
Subject: [PATCH 01/17] Fixing Issue 29128

---
 pandas/core/arrays/integer.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/core/arrays/integer.py b/pandas/core/arrays/integer.py
index 630c3e50f2c09..1899358bbea62 100644
--- a/pandas/core/arrays/integer.py
+++ b/pandas/core/arrays/integer.py
@@ -652,7 +652,7 @@ def _reduce(self, name, skipna=True, **kwargs):
             data[mask] = self._na_value
 
         op = getattr(nanops, "nan" + name)
-        result = op(data, axis=0, skipna=skipna, mask=mask)
+        result = op(data, axis=0, skipna=skipna, mask=mask, **kwargs)
 
         # if we have a boolean op, don't coerce
         if name in ["any", "all"]:

From 35048922d02f6c4c96f1d5a9664e6bc519e5411e Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 15:31:32 +0100
Subject: [PATCH 02/17] added test

---
 pandas/tests/arrays/test_integer.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/pandas/tests/arrays/test_integer.py b/pandas/tests/arrays/test_integer.py
index 793de66767cc3..98ee53e3cd042 100644
--- a/pandas/tests/arrays/test_integer.py
+++ b/pandas/tests/arrays/test_integer.py
@@ -828,6 +828,13 @@ def test_arrow_array(data):
     expected = pa.array(list(data), type=data.dtype.name.lower(), from_pandas=True)
     assert arr.equals(expected)
 
+@pytest.mark.parametrize("ddof", [0, 1])
+def test_var_ddof(ddof):
+    s = pd.Series(data=[1, 2, 3, 4, 5, 6, np.nan, np.nan], dtype="Int64")
+    result = s.var(ddof=ddof)
+    expected = np.var([1, 2, 3, 4, 5, 6, np.nan, np.nan], ddof=ddof)
+    assert expected == result
+
 
 # TODO(jreback) - these need testing / are broken
 

From 897c2b470391b19774643cb41dd92923b3346bbd Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 15:39:41 +0100
Subject: [PATCH 03/17] added whatnew reference

---
 doc/source/whatsnew/v0.25.3.rst | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/doc/source/whatsnew/v0.25.3.rst b/doc/source/whatsnew/v0.25.3.rst
index f73a3f956f42e..aceee7b9bf7f8 100644
--- a/doc/source/whatsnew/v0.25.3.rst
+++ b/doc/source/whatsnew/v0.25.3.rst
@@ -16,6 +16,11 @@ Groupby/resample/rolling
 
 - Bug in :meth:`DataFrameGroupBy.quantile` where NA values in the grouping could cause segfaults or incorrect results (:issue:`28882`)
 
+Series
+^^^^^^
+
+- Bug in :meth:`Series.var` not computing the right value with an integer series with missing values when ddof = 0
+
 Contributors
 ~~~~~~~~~~~~
 

From b3a4aa6dacd344fefac83b372c70e489541b6c12 Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 15:43:19 +0100
Subject: [PATCH 04/17] black pandas

---
 pandas/core/algorithms.py                        |  2 +-
 pandas/core/frame.py                             |  2 +-
 pandas/core/generic.py                           |  2 +-
 pandas/core/groupby/grouper.py                   |  6 +++++-
 pandas/core/indexes/base.py                      |  2 +-
 pandas/core/indexing.py                          |  6 +++---
 pandas/core/internals/managers.py                |  2 +-
 pandas/io/common.py                              |  4 ++--
 pandas/io/parsers.py                             | 14 ++++++++++++--
 pandas/io/stata.py                               |  2 +-
 pandas/tests/arrays/sparse/test_array.py         | 12 ++++++++----
 pandas/tests/arrays/test_integer.py              |  1 +
 pandas/tests/dtypes/test_inference.py            |  2 +-
 pandas/tests/frame/test_constructors.py          |  6 +++---
 pandas/tests/indexes/period/test_construction.py |  2 +-
 pandas/tests/indexing/multiindex/test_getitem.py |  2 +-
 pandas/tests/indexing/multiindex/test_xs.py      |  2 +-
 pandas/tests/indexing/test_callable.py           | 12 +++++++++---
 pandas/tests/io/parser/test_index_col.py         |  4 ++--
 pandas/tests/reductions/test_reductions.py       |  4 ++--
 pandas/tests/test_algos.py                       | 10 +++++-----
 pandas/tests/test_nanops.py                      |  2 +-
 22 files changed, 63 insertions(+), 38 deletions(-)

diff --git a/pandas/core/algorithms.py b/pandas/core/algorithms.py
index c70e623778315..cc6c23929d49c 100644
--- a/pandas/core/algorithms.py
+++ b/pandas/core/algorithms.py
@@ -1155,7 +1155,7 @@ def compute(self, method):
         n = min(n, narr)
 
         kth_val = algos.kth_smallest(arr.copy(), n - 1)
-        ns, = np.nonzero(arr <= kth_val)
+        (ns,) = np.nonzero(arr <= kth_val)
         inds = ns[arr[ns].argsort(kind="mergesort")]
 
         if self.keep != "all":
diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 40efc4c65476a..7d8cc0b731017 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -4829,7 +4829,7 @@ def drop_duplicates(self, subset=None, keep="first", inplace=False):
         duplicated = self.duplicated(subset, keep=keep)
 
         if inplace:
-            inds, = (-duplicated)._ndarray_values.nonzero()
+            (inds,) = (-duplicated)._ndarray_values.nonzero()
             new_data = self._data.take(inds)
             self._update_inplace(new_data)
         else:
diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index f88c26c7bc782..fa43206b86ec4 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -3613,7 +3613,7 @@ class   animal   locomotion
 
             if isinstance(loc, np.ndarray):
                 if loc.dtype == np.bool_:
-                    inds, = loc.nonzero()
+                    (inds,) = loc.nonzero()
                     return self.take(inds, axis=axis)
                 else:
                     return self.take(loc, axis=axis)
diff --git a/pandas/core/groupby/grouper.py b/pandas/core/groupby/grouper.py
index d7eaaca5ac83a..d6beefbf31db7 100644
--- a/pandas/core/groupby/grouper.py
+++ b/pandas/core/groupby/grouper.py
@@ -284,7 +284,11 @@ def __init__(
             if self.name is None:
                 self.name = index.names[level]
 
-            self.grouper, self._labels, self._group_index = index._get_grouper_for_level(  # noqa: E501
+            (
+                self.grouper,
+                self._labels,
+                self._group_index,
+            ) = index._get_grouper_for_level(  # noqa: E501
                 self.grouper, level
             )
 
diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index 187c7e2f3a7f7..954607a0dc6de 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -1873,7 +1873,7 @@ def _isnan(self):
     @cache_readonly
     def _nan_idxs(self):
         if self._can_hold_na:
-            w, = self._isnan.nonzero()
+            (w,) = self._isnan.nonzero()
             return w
         else:
             return np.array([], dtype=np.int64)
diff --git a/pandas/core/indexing.py b/pandas/core/indexing.py
index 44c786f003369..1315e9d5b1c3f 100755
--- a/pandas/core/indexing.py
+++ b/pandas/core/indexing.py
@@ -320,7 +320,7 @@ def _setitem_with_indexer(self, indexer, value):
         # if there is only one block/type, still have to take split path
         # unless the block is one-dimensional or it can hold the value
         if not take_split_path and self.obj._data.blocks:
-            blk, = self.obj._data.blocks
+            (blk,) = self.obj._data.blocks
             if 1 < blk.ndim:  # in case of dict, keys are indices
                 val = list(value.values()) if isinstance(value, dict) else value
                 take_split_path = not blk._can_hold_element(val)
@@ -1120,7 +1120,7 @@ def _getitem_iterable(self, key, axis: int):
         if com.is_bool_indexer(key):
             # A boolean indexer
             key = check_bool_indexer(labels, key)
-            inds, = key.nonzero()
+            (inds,) = key.nonzero()
             return self.obj.take(inds, axis=axis)
         else:
             # A collection of keys
@@ -1264,7 +1264,7 @@ def _convert_to_indexer(self, obj, axis: int, raise_missing: bool = False):
 
             if com.is_bool_indexer(obj):
                 obj = check_bool_indexer(labels, obj)
-                inds, = obj.nonzero()
+                (inds,) = obj.nonzero()
                 return inds
             else:
                 # When setting, missing keys are not allowed, even with .loc:
diff --git a/pandas/core/internals/managers.py b/pandas/core/internals/managers.py
index c47aaf7c773c4..db782b4550907 100644
--- a/pandas/core/internals/managers.py
+++ b/pandas/core/internals/managers.py
@@ -1868,7 +1868,7 @@ def _shape_compat(x):
 
 
 def _interleaved_dtype(
-    blocks: List[Block]
+    blocks: List[Block],
 ) -> Optional[Union[np.dtype, ExtensionDtype]]:
     """Find the common dtype for `blocks`.
 
diff --git a/pandas/io/common.py b/pandas/io/common.py
index 0bef14e4999c7..e08fd37e65ad9 100644
--- a/pandas/io/common.py
+++ b/pandas/io/common.py
@@ -109,7 +109,7 @@ def _is_url(url) -> bool:
 
 
 def _expand_user(
-    filepath_or_buffer: FilePathOrBuffer[AnyStr]
+    filepath_or_buffer: FilePathOrBuffer[AnyStr],
 ) -> FilePathOrBuffer[AnyStr]:
     """Return the argument with an initial component of ~ or ~user
        replaced by that user's home directory.
@@ -139,7 +139,7 @@ def _validate_header_arg(header) -> None:
 
 
 def _stringify_path(
-    filepath_or_buffer: FilePathOrBuffer[AnyStr]
+    filepath_or_buffer: FilePathOrBuffer[AnyStr],
 ) -> FilePathOrBuffer[AnyStr]:
     """Attempt to convert a path-like object to a string.
 
diff --git a/pandas/io/parsers.py b/pandas/io/parsers.py
index 058d65b9464ae..4ff988acfe4da 100755
--- a/pandas/io/parsers.py
+++ b/pandas/io/parsers.py
@@ -1918,7 +1918,12 @@ def __init__(self, src, **kwds):
         else:
             if len(self._reader.header) > 1:
                 # we have a multi index in the columns
-                self.names, self.index_names, self.col_names, passed_names = self._extract_multi_indexer_columns(  # noqa: E501
+                (
+                    self.names,
+                    self.index_names,
+                    self.col_names,
+                    passed_names,
+                ) = self._extract_multi_indexer_columns(  # noqa: E501
                     self._reader.header, self.index_names, self.col_names, passed_names
                 )
             else:
@@ -2307,7 +2312,12 @@ def __init__(self, f, **kwds):
         # The original set is stored in self.original_columns.
         if len(self.columns) > 1:
             # we are processing a multi index column
-            self.columns, self.index_names, self.col_names, _ = self._extract_multi_indexer_columns(  # noqa: E501
+            (
+                self.columns,
+                self.index_names,
+                self.col_names,
+                _,
+            ) = self._extract_multi_indexer_columns(  # noqa: E501
                 self.columns, self.index_names, self.col_names
             )
             # Update list of original names to include all indices.
diff --git a/pandas/io/stata.py b/pandas/io/stata.py
index 07475f224bd5f..8e5fa48d460e8 100644
--- a/pandas/io/stata.py
+++ b/pandas/io/stata.py
@@ -614,7 +614,7 @@ def _cast_to_stata_types(data):
                 data[col] = data[col].astype(np.int32)
             else:
                 data[col] = data[col].astype(np.float64)
-                if data[col].max() >= 2 ** 53 or data[col].min() <= -2 ** 53:
+                if data[col].max() >= 2 ** 53 or data[col].min() <= -(2 ** 53):
                     ws = precision_loss_doc % ("int64", "float64")
         elif dtype in (np.float32, np.float64):
             value = data[col].max()
diff --git a/pandas/tests/arrays/sparse/test_array.py b/pandas/tests/arrays/sparse/test_array.py
index f9bb4981df7df..755cbfb716fcd 100644
--- a/pandas/tests/arrays/sparse/test_array.py
+++ b/pandas/tests/arrays/sparse/test_array.py
@@ -658,12 +658,16 @@ def test_getslice_tuple(self):
         dense = np.array([np.nan, 0, 3, 4, 0, 5, np.nan, np.nan, 0])
 
         sparse = SparseArray(dense)
-        res = sparse[4:,]  # noqa: E231
+        res = sparse[
+            4:,
+        ]  # noqa: E231
         exp = SparseArray(dense[4:,])  # noqa: E231
         tm.assert_sp_array_equal(res, exp)
 
         sparse = SparseArray(dense, fill_value=0)
-        res = sparse[4:,]  # noqa: E231
+        res = sparse[
+            4:,
+        ]  # noqa: E231
         exp = SparseArray(dense[4:,], fill_value=0)  # noqa: E231
         tm.assert_sp_array_equal(res, exp)
 
@@ -823,11 +827,11 @@ def test_nonzero(self):
         # Tests regression #21172.
         sa = pd.SparseArray([float("nan"), float("nan"), 1, 0, 0, 2, 0, 0, 0, 3, 0, 0])
         expected = np.array([2, 5, 9], dtype=np.int32)
-        result, = sa.nonzero()
+        (result,) = sa.nonzero()
         tm.assert_numpy_array_equal(expected, result)
 
         sa = pd.SparseArray([0, 0, 1, 0, 0, 2, 0, 0, 0, 3, 0, 0])
-        result, = sa.nonzero()
+        (result,) = sa.nonzero()
         tm.assert_numpy_array_equal(expected, result)
 
 
diff --git a/pandas/tests/arrays/test_integer.py b/pandas/tests/arrays/test_integer.py
index 98ee53e3cd042..9d1982093b793 100644
--- a/pandas/tests/arrays/test_integer.py
+++ b/pandas/tests/arrays/test_integer.py
@@ -828,6 +828,7 @@ def test_arrow_array(data):
     expected = pa.array(list(data), type=data.dtype.name.lower(), from_pandas=True)
     assert arr.equals(expected)
 
+
 @pytest.mark.parametrize("ddof", [0, 1])
 def test_var_ddof(ddof):
     s = pd.Series(data=[1, 2, 3, 4, 5, 6, np.nan, np.nan], dtype="Int64")
diff --git a/pandas/tests/dtypes/test_inference.py b/pandas/tests/dtypes/test_inference.py
index 62fb118f719e3..7d5b1891cbd32 100644
--- a/pandas/tests/dtypes/test_inference.py
+++ b/pandas/tests/dtypes/test_inference.py
@@ -505,7 +505,7 @@ def test_convert_numeric_int64_uint64(self, case, coerce):
         result = lib.maybe_convert_numeric(case, set(), coerce_numeric=coerce)
         tm.assert_almost_equal(result, expected)
 
-    @pytest.mark.parametrize("value", [-2 ** 63 - 1, 2 ** 64])
+    @pytest.mark.parametrize("value", [-(2 ** 63) - 1, 2 ** 64])
     def test_convert_int_overflow(self, value):
         # see gh-18584
         arr = np.array([value], dtype=object)
diff --git a/pandas/tests/frame/test_constructors.py b/pandas/tests/frame/test_constructors.py
index aa00cf234d9ee..f193f97aedb22 100644
--- a/pandas/tests/frame/test_constructors.py
+++ b/pandas/tests/frame/test_constructors.py
@@ -245,9 +245,9 @@ def test_constructor_overflow_int64(self):
             np.array([2 ** 64], dtype=object),
             np.array([2 ** 65]),
             [2 ** 64 + 1],
-            np.array([-2 ** 63 - 4], dtype=object),
-            np.array([-2 ** 64 - 1]),
-            [-2 ** 65 - 2],
+            np.array([-(2 ** 63) - 4], dtype=object),
+            np.array([-(2 ** 64) - 1]),
+            [-(2 ** 65) - 2],
         ],
     )
     def test_constructor_int_overflow(self, values):
diff --git a/pandas/tests/indexes/period/test_construction.py b/pandas/tests/indexes/period/test_construction.py
index 8c75fbbae7de3..1973cb7f4740d 100644
--- a/pandas/tests/indexes/period/test_construction.py
+++ b/pandas/tests/indexes/period/test_construction.py
@@ -434,7 +434,7 @@ def test_constructor_range_based_deprecated_different_freq(self):
         with tm.assert_produces_warning(FutureWarning) as m:
             PeriodIndex(start="2000", periods=2)
 
-        warning, = m
+        (warning,) = m
         assert 'freq="A-DEC"' in str(warning.message)
 
     def test_constructor(self):
diff --git a/pandas/tests/indexing/multiindex/test_getitem.py b/pandas/tests/indexing/multiindex/test_getitem.py
index 4f95e6bd28989..519a1eb5b16d8 100644
--- a/pandas/tests/indexing/multiindex/test_getitem.py
+++ b/pandas/tests/indexing/multiindex/test_getitem.py
@@ -108,7 +108,7 @@ def test_series_getitem_indexing_errors(
 
 
 def test_series_getitem_corner_generator(
-    multiindex_year_month_day_dataframe_random_data
+    multiindex_year_month_day_dataframe_random_data,
 ):
     s = multiindex_year_month_day_dataframe_random_data["A"]
     result = s[(x > 0 for x in s)]
diff --git a/pandas/tests/indexing/multiindex/test_xs.py b/pandas/tests/indexing/multiindex/test_xs.py
index 99f343c2f4a7d..40483ffec4992 100644
--- a/pandas/tests/indexing/multiindex/test_xs.py
+++ b/pandas/tests/indexing/multiindex/test_xs.py
@@ -211,7 +211,7 @@ def test_xs_level_series_ymd(multiindex_year_month_day_dataframe_random_data):
 
 
 def test_xs_level_series_slice_not_implemented(
-    multiindex_year_month_day_dataframe_random_data
+    multiindex_year_month_day_dataframe_random_data,
 ):
     # this test is not explicitly testing .xs functionality
     # TODO: move to another module or refactor
diff --git a/pandas/tests/indexing/test_callable.py b/pandas/tests/indexing/test_callable.py
index aa73bd728595f..81dedfdc74409 100644
--- a/pandas/tests/indexing/test_callable.py
+++ b/pandas/tests/indexing/test_callable.py
@@ -17,10 +17,14 @@ def test_frame_loc_callable(self):
         res = df.loc[lambda x: x.A > 2]
         tm.assert_frame_equal(res, df.loc[df.A > 2])
 
-        res = df.loc[lambda x: x.A > 2,]  # noqa: E231
+        res = df.loc[
+            lambda x: x.A > 2,
+        ]  # noqa: E231
         tm.assert_frame_equal(res, df.loc[df.A > 2,])  # noqa: E231
 
-        res = df.loc[lambda x: x.A > 2,]  # noqa: E231
+        res = df.loc[
+            lambda x: x.A > 2,
+        ]  # noqa: E231
         tm.assert_frame_equal(res, df.loc[df.A > 2,])  # noqa: E231
 
         res = df.loc[lambda x: x.B == "b", :]
@@ -90,7 +94,9 @@ def test_frame_loc_callable_labels(self):
         res = df.loc[lambda x: ["A", "C"]]
         tm.assert_frame_equal(res, df.loc[["A", "C"]])
 
-        res = df.loc[lambda x: ["A", "C"],]  # noqa: E231
+        res = df.loc[
+            lambda x: ["A", "C"],
+        ]  # noqa: E231
         tm.assert_frame_equal(res, df.loc[["A", "C"],])  # noqa: E231
 
         res = df.loc[lambda x: ["A", "C"], :]
diff --git a/pandas/tests/io/parser/test_index_col.py b/pandas/tests/io/parser/test_index_col.py
index 4dfb8d3bd2dc8..8122559997cce 100644
--- a/pandas/tests/io/parser/test_index_col.py
+++ b/pandas/tests/io/parser/test_index_col.py
@@ -22,8 +22,8 @@ def test_index_col_named(all_parsers, with_header):
 KORD5,19990127, 22:00:00, 21:56:00, -0.5900, 1.7100, 5.1000, 0.0000, 290.0000
 KORD6,19990127, 23:00:00, 22:56:00, -0.5900, 1.7100, 4.6000, 0.0000, 280.0000"""  # noqa
     header = (
-        "ID,date,NominalTime,ActualTime,TDew,TAir,Windspeed,Precip,WindDir\n"
-    )  # noqa
+        "ID,date,NominalTime,ActualTime,TDew,TAir,Windspeed,Precip,WindDir\n"  # noqa
+    )
 
     if with_header:
         data = header + no_header
diff --git a/pandas/tests/reductions/test_reductions.py b/pandas/tests/reductions/test_reductions.py
index 05ebff4387908..9bd6fb41cf366 100644
--- a/pandas/tests/reductions/test_reductions.py
+++ b/pandas/tests/reductions/test_reductions.py
@@ -179,8 +179,8 @@ class TestIndexReductions:
         [
             (0, 400, 3),
             (500, 0, -6),
-            (-10 ** 6, 10 ** 6, 4),
-            (10 ** 6, -10 ** 6, -4),
+            (-(10 ** 6), 10 ** 6, 4),
+            (10 ** 6, -(10 ** 6), -4),
             (0, 10, 20),
         ],
     )
diff --git a/pandas/tests/test_algos.py b/pandas/tests/test_algos.py
index 9dd88fd5dd25b..885428e5146b2 100644
--- a/pandas/tests/test_algos.py
+++ b/pandas/tests/test_algos.py
@@ -216,10 +216,10 @@ def test_uint64_factorize(self, writable):
         tm.assert_numpy_array_equal(uniques, exp_uniques)
 
     def test_int64_factorize(self, writable):
-        data = np.array([2 ** 63 - 1, -2 ** 63, 2 ** 63 - 1], dtype=np.int64)
+        data = np.array([2 ** 63 - 1, -(2 ** 63), 2 ** 63 - 1], dtype=np.int64)
         data.setflags(write=writable)
         exp_labels = np.array([0, 1, 0], dtype=np.intp)
-        exp_uniques = np.array([2 ** 63 - 1, -2 ** 63], dtype=np.int64)
+        exp_uniques = np.array([2 ** 63 - 1, -(2 ** 63)], dtype=np.int64)
 
         labels, uniques = algos.factorize(data)
         tm.assert_numpy_array_equal(labels, exp_labels)
@@ -258,7 +258,7 @@ def test_deprecate_order(self):
         "data",
         [
             np.array([0, 1, 0], dtype="u8"),
-            np.array([-2 ** 63, 1, -2 ** 63], dtype="i8"),
+            np.array([-(2 ** 63), 1, -(2 ** 63)], dtype="i8"),
             np.array(["__nan__", "foo", "__nan__"], dtype="object"),
         ],
     )
@@ -275,8 +275,8 @@ def test_parametrized_factorize_na_value_default(self, data):
         [
             (np.array([0, 1, 0, 2], dtype="u8"), 0),
             (np.array([1, 0, 1, 2], dtype="u8"), 1),
-            (np.array([-2 ** 63, 1, -2 ** 63, 0], dtype="i8"), -2 ** 63),
-            (np.array([1, -2 ** 63, 1, 0], dtype="i8"), 1),
+            (np.array([-(2 ** 63), 1, -(2 ** 63), 0], dtype="i8"), -(2 ** 63)),
+            (np.array([1, -(2 ** 63), 1, 0], dtype="i8"), 1),
             (np.array(["a", "", "a", "b"], dtype=object), "a"),
             (np.array([(), ("a", 1), (), ("a", 2)], dtype=object), ()),
             (np.array([("a", 1), (), ("a", 1), ("a", 2)], dtype=object), ("a", 1)),
diff --git a/pandas/tests/test_nanops.py b/pandas/tests/test_nanops.py
index 49d1777df0751..e6cff5c266bc6 100644
--- a/pandas/tests/test_nanops.py
+++ b/pandas/tests/test_nanops.py
@@ -302,7 +302,7 @@ def test_nanmean_overflow(self):
         # In the previous implementation mean can overflow for int dtypes, it
         # is now consistent with numpy
 
-        for a in [2 ** 55, -2 ** 55, 20150515061816532]:
+        for a in [2 ** 55, -(2 ** 55), 20150515061816532]:
             s = Series(a, index=range(500), dtype=np.int64)
             result = s.mean()
             np_result = s.values.mean()

From 92c0bb1c85059d4277fdcc9ed03309afb8e8ea93 Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 15:52:31 +0100
Subject: [PATCH 05/17] Minor Changes

---
 pandas/tests/arrays/test_integer.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/pandas/tests/arrays/test_integer.py b/pandas/tests/arrays/test_integer.py
index 9d1982093b793..98ee53e3cd042 100644
--- a/pandas/tests/arrays/test_integer.py
+++ b/pandas/tests/arrays/test_integer.py
@@ -828,7 +828,6 @@ def test_arrow_array(data):
     expected = pa.array(list(data), type=data.dtype.name.lower(), from_pandas=True)
     assert arr.equals(expected)
 
-
 @pytest.mark.parametrize("ddof", [0, 1])
 def test_var_ddof(ddof):
     s = pd.Series(data=[1, 2, 3, 4, 5, 6, np.nan, np.nan], dtype="Int64")

From 2da83e45252df7fe21f7bf6d34ea6b75654fdd3d Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 16:53:25 +0100
Subject: [PATCH 06/17] added whatsnew

---
 doc/source/whatsnew/v1.0.0.rst | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v1.0.0.rst b/doc/source/whatsnew/v1.0.0.rst
index fa1669b1f3343..486740f0ca3d0 100644
--- a/doc/source/whatsnew/v1.0.0.rst
+++ b/doc/source/whatsnew/v1.0.0.rst
@@ -324,7 +324,8 @@ Numeric
 - :class:`DataFrame` flex inequality comparisons methods (:meth:`DataFrame.lt`, :meth:`DataFrame.le`, :meth:`DataFrame.gt`, :meth: `DataFrame.ge`) with object-dtype and ``complex`` entries failing to raise ``TypeError`` like their :class:`Series` counterparts (:issue:`28079`)
 - Bug in :class:`DataFrame` logical operations (`&`, `|`, `^`) not matching :class:`Series` behavior by filling NA values (:issue:`28741`)
 - Bug in :meth:`DataFrame.interpolate` where specifying axis by name references variable before it is assigned (:issue:`29142`)
--
+- Bug in :meth:`Series.var` not computing the right value with an integer series with missing values when ddof = 0 (:issue:`29128`)
+- 
 
 Conversion
 ^^^^^^^^^^

From 5e4f73d90dcf244a76f2c6a1cf4381d96efbd02a Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 17:10:12 +0100
Subject: [PATCH 07/17] Revert "added test"

This reverts commit 35048922d02f6c4c96f1d5a9664e6bc519e5411e.
---
 pandas/tests/arrays/test_integer.py | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/pandas/tests/arrays/test_integer.py b/pandas/tests/arrays/test_integer.py
index 98ee53e3cd042..793de66767cc3 100644
--- a/pandas/tests/arrays/test_integer.py
+++ b/pandas/tests/arrays/test_integer.py
@@ -828,13 +828,6 @@ def test_arrow_array(data):
     expected = pa.array(list(data), type=data.dtype.name.lower(), from_pandas=True)
     assert arr.equals(expected)
 
-@pytest.mark.parametrize("ddof", [0, 1])
-def test_var_ddof(ddof):
-    s = pd.Series(data=[1, 2, 3, 4, 5, 6, np.nan, np.nan], dtype="Int64")
-    result = s.var(ddof=ddof)
-    expected = np.var([1, 2, 3, 4, 5, 6, np.nan, np.nan], ddof=ddof)
-    assert expected == result
-
 
 # TODO(jreback) - these need testing / are broken
 

From 14808f063056d7eb23672ede1512f8e23169b9eb Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 17:18:33 +0100
Subject: [PATCH 08/17] Revert "added whatsnew"

This reverts commit 2da83e45252df7fe21f7bf6d34ea6b75654fdd3d.
---
 doc/source/whatsnew/v1.0.0.rst | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/doc/source/whatsnew/v1.0.0.rst b/doc/source/whatsnew/v1.0.0.rst
index 486740f0ca3d0..fa1669b1f3343 100644
--- a/doc/source/whatsnew/v1.0.0.rst
+++ b/doc/source/whatsnew/v1.0.0.rst
@@ -324,8 +324,7 @@ Numeric
 - :class:`DataFrame` flex inequality comparisons methods (:meth:`DataFrame.lt`, :meth:`DataFrame.le`, :meth:`DataFrame.gt`, :meth: `DataFrame.ge`) with object-dtype and ``complex`` entries failing to raise ``TypeError`` like their :class:`Series` counterparts (:issue:`28079`)
 - Bug in :class:`DataFrame` logical operations (`&`, `|`, `^`) not matching :class:`Series` behavior by filling NA values (:issue:`28741`)
 - Bug in :meth:`DataFrame.interpolate` where specifying axis by name references variable before it is assigned (:issue:`29142`)
-- Bug in :meth:`Series.var` not computing the right value with an integer series with missing values when ddof = 0 (:issue:`29128`)
-- 
+-
 
 Conversion
 ^^^^^^^^^^

From 2bacae79767dd9f4890ec9c6b1be9dfb55b727a7 Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 17:21:45 +0100
Subject: [PATCH 09/17] Revert "black pandas"

This reverts commit b3a4aa6dacd344fefac83b372c70e489541b6c12.
---
 pandas/core/algorithms.py                        |  2 +-
 pandas/core/frame.py                             |  2 +-
 pandas/core/generic.py                           |  2 +-
 pandas/core/groupby/grouper.py                   |  6 +-----
 pandas/core/indexes/base.py                      |  2 +-
 pandas/core/indexing.py                          |  6 +++---
 pandas/core/internals/managers.py                |  2 +-
 pandas/io/common.py                              |  4 ++--
 pandas/io/parsers.py                             | 14 ++------------
 pandas/io/stata.py                               |  2 +-
 pandas/tests/arrays/sparse/test_array.py         | 12 ++++--------
 pandas/tests/arrays/test_integer.py              |  8 ++++++++
 pandas/tests/dtypes/test_inference.py            |  2 +-
 pandas/tests/frame/test_constructors.py          |  6 +++---
 pandas/tests/indexes/period/test_construction.py |  2 +-
 pandas/tests/indexing/multiindex/test_getitem.py |  2 +-
 pandas/tests/indexing/multiindex/test_xs.py      |  2 +-
 pandas/tests/indexing/test_callable.py           | 12 +++---------
 pandas/tests/io/parser/test_index_col.py         |  4 ++--
 pandas/tests/reductions/test_reductions.py       |  4 ++--
 pandas/tests/test_algos.py                       | 10 +++++-----
 pandas/tests/test_nanops.py                      |  2 +-
 22 files changed, 46 insertions(+), 62 deletions(-)

diff --git a/pandas/core/algorithms.py b/pandas/core/algorithms.py
index cc6c23929d49c..c70e623778315 100644
--- a/pandas/core/algorithms.py
+++ b/pandas/core/algorithms.py
@@ -1155,7 +1155,7 @@ def compute(self, method):
         n = min(n, narr)
 
         kth_val = algos.kth_smallest(arr.copy(), n - 1)
-        (ns,) = np.nonzero(arr <= kth_val)
+        ns, = np.nonzero(arr <= kth_val)
         inds = ns[arr[ns].argsort(kind="mergesort")]
 
         if self.keep != "all":
diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 7d8cc0b731017..40efc4c65476a 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -4829,7 +4829,7 @@ def drop_duplicates(self, subset=None, keep="first", inplace=False):
         duplicated = self.duplicated(subset, keep=keep)
 
         if inplace:
-            (inds,) = (-duplicated)._ndarray_values.nonzero()
+            inds, = (-duplicated)._ndarray_values.nonzero()
             new_data = self._data.take(inds)
             self._update_inplace(new_data)
         else:
diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index fa43206b86ec4..f88c26c7bc782 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -3613,7 +3613,7 @@ class   animal   locomotion
 
             if isinstance(loc, np.ndarray):
                 if loc.dtype == np.bool_:
-                    (inds,) = loc.nonzero()
+                    inds, = loc.nonzero()
                     return self.take(inds, axis=axis)
                 else:
                     return self.take(loc, axis=axis)
diff --git a/pandas/core/groupby/grouper.py b/pandas/core/groupby/grouper.py
index d6beefbf31db7..d7eaaca5ac83a 100644
--- a/pandas/core/groupby/grouper.py
+++ b/pandas/core/groupby/grouper.py
@@ -284,11 +284,7 @@ def __init__(
             if self.name is None:
                 self.name = index.names[level]
 
-            (
-                self.grouper,
-                self._labels,
-                self._group_index,
-            ) = index._get_grouper_for_level(  # noqa: E501
+            self.grouper, self._labels, self._group_index = index._get_grouper_for_level(  # noqa: E501
                 self.grouper, level
             )
 
diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index 954607a0dc6de..187c7e2f3a7f7 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -1873,7 +1873,7 @@ def _isnan(self):
     @cache_readonly
     def _nan_idxs(self):
         if self._can_hold_na:
-            (w,) = self._isnan.nonzero()
+            w, = self._isnan.nonzero()
             return w
         else:
             return np.array([], dtype=np.int64)
diff --git a/pandas/core/indexing.py b/pandas/core/indexing.py
index 1315e9d5b1c3f..44c786f003369 100755
--- a/pandas/core/indexing.py
+++ b/pandas/core/indexing.py
@@ -320,7 +320,7 @@ def _setitem_with_indexer(self, indexer, value):
         # if there is only one block/type, still have to take split path
         # unless the block is one-dimensional or it can hold the value
         if not take_split_path and self.obj._data.blocks:
-            (blk,) = self.obj._data.blocks
+            blk, = self.obj._data.blocks
             if 1 < blk.ndim:  # in case of dict, keys are indices
                 val = list(value.values()) if isinstance(value, dict) else value
                 take_split_path = not blk._can_hold_element(val)
@@ -1120,7 +1120,7 @@ def _getitem_iterable(self, key, axis: int):
         if com.is_bool_indexer(key):
             # A boolean indexer
             key = check_bool_indexer(labels, key)
-            (inds,) = key.nonzero()
+            inds, = key.nonzero()
             return self.obj.take(inds, axis=axis)
         else:
             # A collection of keys
@@ -1264,7 +1264,7 @@ def _convert_to_indexer(self, obj, axis: int, raise_missing: bool = False):
 
             if com.is_bool_indexer(obj):
                 obj = check_bool_indexer(labels, obj)
-                (inds,) = obj.nonzero()
+                inds, = obj.nonzero()
                 return inds
             else:
                 # When setting, missing keys are not allowed, even with .loc:
diff --git a/pandas/core/internals/managers.py b/pandas/core/internals/managers.py
index db782b4550907..c47aaf7c773c4 100644
--- a/pandas/core/internals/managers.py
+++ b/pandas/core/internals/managers.py
@@ -1868,7 +1868,7 @@ def _shape_compat(x):
 
 
 def _interleaved_dtype(
-    blocks: List[Block],
+    blocks: List[Block]
 ) -> Optional[Union[np.dtype, ExtensionDtype]]:
     """Find the common dtype for `blocks`.
 
diff --git a/pandas/io/common.py b/pandas/io/common.py
index e08fd37e65ad9..0bef14e4999c7 100644
--- a/pandas/io/common.py
+++ b/pandas/io/common.py
@@ -109,7 +109,7 @@ def _is_url(url) -> bool:
 
 
 def _expand_user(
-    filepath_or_buffer: FilePathOrBuffer[AnyStr],
+    filepath_or_buffer: FilePathOrBuffer[AnyStr]
 ) -> FilePathOrBuffer[AnyStr]:
     """Return the argument with an initial component of ~ or ~user
        replaced by that user's home directory.
@@ -139,7 +139,7 @@ def _validate_header_arg(header) -> None:
 
 
 def _stringify_path(
-    filepath_or_buffer: FilePathOrBuffer[AnyStr],
+    filepath_or_buffer: FilePathOrBuffer[AnyStr]
 ) -> FilePathOrBuffer[AnyStr]:
     """Attempt to convert a path-like object to a string.
 
diff --git a/pandas/io/parsers.py b/pandas/io/parsers.py
index 4ff988acfe4da..058d65b9464ae 100755
--- a/pandas/io/parsers.py
+++ b/pandas/io/parsers.py
@@ -1918,12 +1918,7 @@ def __init__(self, src, **kwds):
         else:
             if len(self._reader.header) > 1:
                 # we have a multi index in the columns
-                (
-                    self.names,
-                    self.index_names,
-                    self.col_names,
-                    passed_names,
-                ) = self._extract_multi_indexer_columns(  # noqa: E501
+                self.names, self.index_names, self.col_names, passed_names = self._extract_multi_indexer_columns(  # noqa: E501
                     self._reader.header, self.index_names, self.col_names, passed_names
                 )
             else:
@@ -2312,12 +2307,7 @@ def __init__(self, f, **kwds):
         # The original set is stored in self.original_columns.
         if len(self.columns) > 1:
             # we are processing a multi index column
-            (
-                self.columns,
-                self.index_names,
-                self.col_names,
-                _,
-            ) = self._extract_multi_indexer_columns(  # noqa: E501
+            self.columns, self.index_names, self.col_names, _ = self._extract_multi_indexer_columns(  # noqa: E501
                 self.columns, self.index_names, self.col_names
             )
             # Update list of original names to include all indices.
diff --git a/pandas/io/stata.py b/pandas/io/stata.py
index 8e5fa48d460e8..07475f224bd5f 100644
--- a/pandas/io/stata.py
+++ b/pandas/io/stata.py
@@ -614,7 +614,7 @@ def _cast_to_stata_types(data):
                 data[col] = data[col].astype(np.int32)
             else:
                 data[col] = data[col].astype(np.float64)
-                if data[col].max() >= 2 ** 53 or data[col].min() <= -(2 ** 53):
+                if data[col].max() >= 2 ** 53 or data[col].min() <= -2 ** 53:
                     ws = precision_loss_doc % ("int64", "float64")
         elif dtype in (np.float32, np.float64):
             value = data[col].max()
diff --git a/pandas/tests/arrays/sparse/test_array.py b/pandas/tests/arrays/sparse/test_array.py
index 755cbfb716fcd..f9bb4981df7df 100644
--- a/pandas/tests/arrays/sparse/test_array.py
+++ b/pandas/tests/arrays/sparse/test_array.py
@@ -658,16 +658,12 @@ def test_getslice_tuple(self):
         dense = np.array([np.nan, 0, 3, 4, 0, 5, np.nan, np.nan, 0])
 
         sparse = SparseArray(dense)
-        res = sparse[
-            4:,
-        ]  # noqa: E231
+        res = sparse[4:,]  # noqa: E231
         exp = SparseArray(dense[4:,])  # noqa: E231
         tm.assert_sp_array_equal(res, exp)
 
         sparse = SparseArray(dense, fill_value=0)
-        res = sparse[
-            4:,
-        ]  # noqa: E231
+        res = sparse[4:,]  # noqa: E231
         exp = SparseArray(dense[4:,], fill_value=0)  # noqa: E231
         tm.assert_sp_array_equal(res, exp)
 
@@ -827,11 +823,11 @@ def test_nonzero(self):
         # Tests regression #21172.
         sa = pd.SparseArray([float("nan"), float("nan"), 1, 0, 0, 2, 0, 0, 0, 3, 0, 0])
         expected = np.array([2, 5, 9], dtype=np.int32)
-        (result,) = sa.nonzero()
+        result, = sa.nonzero()
         tm.assert_numpy_array_equal(expected, result)
 
         sa = pd.SparseArray([0, 0, 1, 0, 0, 2, 0, 0, 0, 3, 0, 0])
-        (result,) = sa.nonzero()
+        result, = sa.nonzero()
         tm.assert_numpy_array_equal(expected, result)
 
 
diff --git a/pandas/tests/arrays/test_integer.py b/pandas/tests/arrays/test_integer.py
index 793de66767cc3..9d1982093b793 100644
--- a/pandas/tests/arrays/test_integer.py
+++ b/pandas/tests/arrays/test_integer.py
@@ -829,6 +829,14 @@ def test_arrow_array(data):
     assert arr.equals(expected)
 
 
+@pytest.mark.parametrize("ddof", [0, 1])
+def test_var_ddof(ddof):
+    s = pd.Series(data=[1, 2, 3, 4, 5, 6, np.nan, np.nan], dtype="Int64")
+    result = s.var(ddof=ddof)
+    expected = np.var([1, 2, 3, 4, 5, 6, np.nan, np.nan], ddof=ddof)
+    assert expected == result
+
+
 # TODO(jreback) - these need testing / are broken
 
 # shift
diff --git a/pandas/tests/dtypes/test_inference.py b/pandas/tests/dtypes/test_inference.py
index 7d5b1891cbd32..62fb118f719e3 100644
--- a/pandas/tests/dtypes/test_inference.py
+++ b/pandas/tests/dtypes/test_inference.py
@@ -505,7 +505,7 @@ def test_convert_numeric_int64_uint64(self, case, coerce):
         result = lib.maybe_convert_numeric(case, set(), coerce_numeric=coerce)
         tm.assert_almost_equal(result, expected)
 
-    @pytest.mark.parametrize("value", [-(2 ** 63) - 1, 2 ** 64])
+    @pytest.mark.parametrize("value", [-2 ** 63 - 1, 2 ** 64])
     def test_convert_int_overflow(self, value):
         # see gh-18584
         arr = np.array([value], dtype=object)
diff --git a/pandas/tests/frame/test_constructors.py b/pandas/tests/frame/test_constructors.py
index f193f97aedb22..aa00cf234d9ee 100644
--- a/pandas/tests/frame/test_constructors.py
+++ b/pandas/tests/frame/test_constructors.py
@@ -245,9 +245,9 @@ def test_constructor_overflow_int64(self):
             np.array([2 ** 64], dtype=object),
             np.array([2 ** 65]),
             [2 ** 64 + 1],
-            np.array([-(2 ** 63) - 4], dtype=object),
-            np.array([-(2 ** 64) - 1]),
-            [-(2 ** 65) - 2],
+            np.array([-2 ** 63 - 4], dtype=object),
+            np.array([-2 ** 64 - 1]),
+            [-2 ** 65 - 2],
         ],
     )
     def test_constructor_int_overflow(self, values):
diff --git a/pandas/tests/indexes/period/test_construction.py b/pandas/tests/indexes/period/test_construction.py
index 1973cb7f4740d..8c75fbbae7de3 100644
--- a/pandas/tests/indexes/period/test_construction.py
+++ b/pandas/tests/indexes/period/test_construction.py
@@ -434,7 +434,7 @@ def test_constructor_range_based_deprecated_different_freq(self):
         with tm.assert_produces_warning(FutureWarning) as m:
             PeriodIndex(start="2000", periods=2)
 
-        (warning,) = m
+        warning, = m
         assert 'freq="A-DEC"' in str(warning.message)
 
     def test_constructor(self):
diff --git a/pandas/tests/indexing/multiindex/test_getitem.py b/pandas/tests/indexing/multiindex/test_getitem.py
index 519a1eb5b16d8..4f95e6bd28989 100644
--- a/pandas/tests/indexing/multiindex/test_getitem.py
+++ b/pandas/tests/indexing/multiindex/test_getitem.py
@@ -108,7 +108,7 @@ def test_series_getitem_indexing_errors(
 
 
 def test_series_getitem_corner_generator(
-    multiindex_year_month_day_dataframe_random_data,
+    multiindex_year_month_day_dataframe_random_data
 ):
     s = multiindex_year_month_day_dataframe_random_data["A"]
     result = s[(x > 0 for x in s)]
diff --git a/pandas/tests/indexing/multiindex/test_xs.py b/pandas/tests/indexing/multiindex/test_xs.py
index 40483ffec4992..99f343c2f4a7d 100644
--- a/pandas/tests/indexing/multiindex/test_xs.py
+++ b/pandas/tests/indexing/multiindex/test_xs.py
@@ -211,7 +211,7 @@ def test_xs_level_series_ymd(multiindex_year_month_day_dataframe_random_data):
 
 
 def test_xs_level_series_slice_not_implemented(
-    multiindex_year_month_day_dataframe_random_data,
+    multiindex_year_month_day_dataframe_random_data
 ):
     # this test is not explicitly testing .xs functionality
     # TODO: move to another module or refactor
diff --git a/pandas/tests/indexing/test_callable.py b/pandas/tests/indexing/test_callable.py
index 81dedfdc74409..aa73bd728595f 100644
--- a/pandas/tests/indexing/test_callable.py
+++ b/pandas/tests/indexing/test_callable.py
@@ -17,14 +17,10 @@ def test_frame_loc_callable(self):
         res = df.loc[lambda x: x.A > 2]
         tm.assert_frame_equal(res, df.loc[df.A > 2])
 
-        res = df.loc[
-            lambda x: x.A > 2,
-        ]  # noqa: E231
+        res = df.loc[lambda x: x.A > 2,]  # noqa: E231
         tm.assert_frame_equal(res, df.loc[df.A > 2,])  # noqa: E231
 
-        res = df.loc[
-            lambda x: x.A > 2,
-        ]  # noqa: E231
+        res = df.loc[lambda x: x.A > 2,]  # noqa: E231
         tm.assert_frame_equal(res, df.loc[df.A > 2,])  # noqa: E231
 
         res = df.loc[lambda x: x.B == "b", :]
@@ -94,9 +90,7 @@ def test_frame_loc_callable_labels(self):
         res = df.loc[lambda x: ["A", "C"]]
         tm.assert_frame_equal(res, df.loc[["A", "C"]])
 
-        res = df.loc[
-            lambda x: ["A", "C"],
-        ]  # noqa: E231
+        res = df.loc[lambda x: ["A", "C"],]  # noqa: E231
         tm.assert_frame_equal(res, df.loc[["A", "C"],])  # noqa: E231
 
         res = df.loc[lambda x: ["A", "C"], :]
diff --git a/pandas/tests/io/parser/test_index_col.py b/pandas/tests/io/parser/test_index_col.py
index 8122559997cce..4dfb8d3bd2dc8 100644
--- a/pandas/tests/io/parser/test_index_col.py
+++ b/pandas/tests/io/parser/test_index_col.py
@@ -22,8 +22,8 @@ def test_index_col_named(all_parsers, with_header):
 KORD5,19990127, 22:00:00, 21:56:00, -0.5900, 1.7100, 5.1000, 0.0000, 290.0000
 KORD6,19990127, 23:00:00, 22:56:00, -0.5900, 1.7100, 4.6000, 0.0000, 280.0000"""  # noqa
     header = (
-        "ID,date,NominalTime,ActualTime,TDew,TAir,Windspeed,Precip,WindDir\n"  # noqa
-    )
+        "ID,date,NominalTime,ActualTime,TDew,TAir,Windspeed,Precip,WindDir\n"
+    )  # noqa
 
     if with_header:
         data = header + no_header
diff --git a/pandas/tests/reductions/test_reductions.py b/pandas/tests/reductions/test_reductions.py
index 9bd6fb41cf366..05ebff4387908 100644
--- a/pandas/tests/reductions/test_reductions.py
+++ b/pandas/tests/reductions/test_reductions.py
@@ -179,8 +179,8 @@ class TestIndexReductions:
         [
             (0, 400, 3),
             (500, 0, -6),
-            (-(10 ** 6), 10 ** 6, 4),
-            (10 ** 6, -(10 ** 6), -4),
+            (-10 ** 6, 10 ** 6, 4),
+            (10 ** 6, -10 ** 6, -4),
             (0, 10, 20),
         ],
     )
diff --git a/pandas/tests/test_algos.py b/pandas/tests/test_algos.py
index 885428e5146b2..9dd88fd5dd25b 100644
--- a/pandas/tests/test_algos.py
+++ b/pandas/tests/test_algos.py
@@ -216,10 +216,10 @@ def test_uint64_factorize(self, writable):
         tm.assert_numpy_array_equal(uniques, exp_uniques)
 
     def test_int64_factorize(self, writable):
-        data = np.array([2 ** 63 - 1, -(2 ** 63), 2 ** 63 - 1], dtype=np.int64)
+        data = np.array([2 ** 63 - 1, -2 ** 63, 2 ** 63 - 1], dtype=np.int64)
         data.setflags(write=writable)
         exp_labels = np.array([0, 1, 0], dtype=np.intp)
-        exp_uniques = np.array([2 ** 63 - 1, -(2 ** 63)], dtype=np.int64)
+        exp_uniques = np.array([2 ** 63 - 1, -2 ** 63], dtype=np.int64)
 
         labels, uniques = algos.factorize(data)
         tm.assert_numpy_array_equal(labels, exp_labels)
@@ -258,7 +258,7 @@ def test_deprecate_order(self):
         "data",
         [
             np.array([0, 1, 0], dtype="u8"),
-            np.array([-(2 ** 63), 1, -(2 ** 63)], dtype="i8"),
+            np.array([-2 ** 63, 1, -2 ** 63], dtype="i8"),
             np.array(["__nan__", "foo", "__nan__"], dtype="object"),
         ],
     )
@@ -275,8 +275,8 @@ def test_parametrized_factorize_na_value_default(self, data):
         [
             (np.array([0, 1, 0, 2], dtype="u8"), 0),
             (np.array([1, 0, 1, 2], dtype="u8"), 1),
-            (np.array([-(2 ** 63), 1, -(2 ** 63), 0], dtype="i8"), -(2 ** 63)),
-            (np.array([1, -(2 ** 63), 1, 0], dtype="i8"), 1),
+            (np.array([-2 ** 63, 1, -2 ** 63, 0], dtype="i8"), -2 ** 63),
+            (np.array([1, -2 ** 63, 1, 0], dtype="i8"), 1),
             (np.array(["a", "", "a", "b"], dtype=object), "a"),
             (np.array([(), ("a", 1), (), ("a", 2)], dtype=object), ()),
             (np.array([("a", 1), (), ("a", 1), ("a", 2)], dtype=object), ("a", 1)),
diff --git a/pandas/tests/test_nanops.py b/pandas/tests/test_nanops.py
index e6cff5c266bc6..49d1777df0751 100644
--- a/pandas/tests/test_nanops.py
+++ b/pandas/tests/test_nanops.py
@@ -302,7 +302,7 @@ def test_nanmean_overflow(self):
         # In the previous implementation mean can overflow for int dtypes, it
         # is now consistent with numpy
 
-        for a in [2 ** 55, -(2 ** 55), 20150515061816532]:
+        for a in [2 ** 55, -2 ** 55, 20150515061816532]:
             s = Series(a, index=range(500), dtype=np.int64)
             result = s.mean()
             np_result = s.values.mean()

From b5f52f47d81e639947e34fd2299c2c161932448e Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 17:25:43 +0100
Subject: [PATCH 10/17] whatsnew fix

---
 doc/source/whatsnew/v0.25.3.rst | 4 ----
 doc/source/whatsnew/v1.0.0.rst  | 2 +-
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/doc/source/whatsnew/v0.25.3.rst b/doc/source/whatsnew/v0.25.3.rst
index aceee7b9bf7f8..9f7eac40ac2af 100644
--- a/doc/source/whatsnew/v0.25.3.rst
+++ b/doc/source/whatsnew/v0.25.3.rst
@@ -16,10 +16,6 @@ Groupby/resample/rolling
 
 - Bug in :meth:`DataFrameGroupBy.quantile` where NA values in the grouping could cause segfaults or incorrect results (:issue:`28882`)
 
-Series
-^^^^^^
-
-- Bug in :meth:`Series.var` not computing the right value with an integer series with missing values when ddof = 0
 
 Contributors
 ~~~~~~~~~~~~
diff --git a/doc/source/whatsnew/v1.0.0.rst b/doc/source/whatsnew/v1.0.0.rst
index fa1669b1f3343..6b78845b5a305 100644
--- a/doc/source/whatsnew/v1.0.0.rst
+++ b/doc/source/whatsnew/v1.0.0.rst
@@ -324,7 +324,7 @@ Numeric
 - :class:`DataFrame` flex inequality comparisons methods (:meth:`DataFrame.lt`, :meth:`DataFrame.le`, :meth:`DataFrame.gt`, :meth: `DataFrame.ge`) with object-dtype and ``complex`` entries failing to raise ``TypeError`` like their :class:`Series` counterparts (:issue:`28079`)
 - Bug in :class:`DataFrame` logical operations (`&`, `|`, `^`) not matching :class:`Series` behavior by filling NA values (:issue:`28741`)
 - Bug in :meth:`DataFrame.interpolate` where specifying axis by name references variable before it is assigned (:issue:`29142`)
--
+- Bug in :meth:`Series.var` not computing the right value with an integer series with missing values when ddof = 0 (:issue:`29128`)
 
 Conversion
 ^^^^^^^^^^

From 474a3621397ab670b062e9abe0ac5b3598a17c09 Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sat, 2 Nov 2019 17:28:13 +0100
Subject: [PATCH 11/17] minor changes

---
 doc/source/whatsnew/v0.25.3.rst | 1 -
 1 file changed, 1 deletion(-)

diff --git a/doc/source/whatsnew/v0.25.3.rst b/doc/source/whatsnew/v0.25.3.rst
index 9f7eac40ac2af..f73a3f956f42e 100644
--- a/doc/source/whatsnew/v0.25.3.rst
+++ b/doc/source/whatsnew/v0.25.3.rst
@@ -16,7 +16,6 @@ Groupby/resample/rolling
 
 - Bug in :meth:`DataFrameGroupBy.quantile` where NA values in the grouping could cause segfaults or incorrect results (:issue:`28882`)
 
-
 Contributors
 ~~~~~~~~~~~~
 

From b39d40dca85027b46e9f0b76c055a7c6f0fc55d2 Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Sun, 3 Nov 2019 17:51:07 +0100
Subject: [PATCH 12/17] test modified

---
 pandas/tests/arrays/test_integer.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/tests/arrays/test_integer.py b/pandas/tests/arrays/test_integer.py
index 9d1982093b793..0571299e54cee 100644
--- a/pandas/tests/arrays/test_integer.py
+++ b/pandas/tests/arrays/test_integer.py
@@ -833,7 +833,7 @@ def test_arrow_array(data):
 def test_var_ddof(ddof):
     s = pd.Series(data=[1, 2, 3, 4, 5, 6, np.nan, np.nan], dtype="Int64")
     result = s.var(ddof=ddof)
-    expected = np.var([1, 2, 3, 4, 5, 6, np.nan, np.nan], ddof=ddof)
+    expected = np.nanvar([1, 2, 3, 4, 5, 6, np.nan, np.nan], ddof=ddof)
     assert expected == result
 
 

From d38f87bfe6c43359bff49b4f852e62ed945ccfaf Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Tue, 5 Nov 2019 01:09:45 +0100
Subject: [PATCH 13/17] fixing whatsnew

---
 doc/source/whatsnew/v1.0.0.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v1.0.0.rst b/doc/source/whatsnew/v1.0.0.rst
index 6b78845b5a305..fc1d2de37a1ce 100644
--- a/doc/source/whatsnew/v1.0.0.rst
+++ b/doc/source/whatsnew/v1.0.0.rst
@@ -324,7 +324,7 @@ Numeric
 - :class:`DataFrame` flex inequality comparisons methods (:meth:`DataFrame.lt`, :meth:`DataFrame.le`, :meth:`DataFrame.gt`, :meth: `DataFrame.ge`) with object-dtype and ``complex`` entries failing to raise ``TypeError`` like their :class:`Series` counterparts (:issue:`28079`)
 - Bug in :class:`DataFrame` logical operations (`&`, `|`, `^`) not matching :class:`Series` behavior by filling NA values (:issue:`28741`)
 - Bug in :meth:`DataFrame.interpolate` where specifying axis by name references variable before it is assigned (:issue:`29142`)
-- Bug in :meth:`Series.var` not computing the right value with an integer series with missing values when ddof = 0 (:issue:`29128`)
+- Bug in :meth:`Series.var` not computing the right value with a nullable integer dtype series not passing through ddof argument (:issue:`29128`)
 
 Conversion
 ^^^^^^^^^^

From c38623f5e947ab5f2b5d6c1c7c5909398b377ced Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Tue, 5 Nov 2019 02:26:04 +0100
Subject: [PATCH 14/17] test updated

---
 pandas/tests/arrays/test_integer.py | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/pandas/tests/arrays/test_integer.py b/pandas/tests/arrays/test_integer.py
index 0571299e54cee..a98142673bf56 100644
--- a/pandas/tests/arrays/test_integer.py
+++ b/pandas/tests/arrays/test_integer.py
@@ -1,5 +1,6 @@
 import numpy as np
 import pytest
+from scipy.stats import kurtosis, skew, sem
 
 import pandas.util._test_decorators as td
 
@@ -829,13 +830,18 @@ def test_arrow_array(data):
     assert arr.equals(expected)
 
 
-@pytest.mark.parametrize("ddof", [0, 1])
-def test_var_ddof(ddof):
+@pytest.mark.parametrize("pandasmethname, npfunction, kwargs, np_kwargs",
+                         [("var",  np.nanvar, {'ddof': 0}, {'ddof': 0}),
+                          ("var",  np.nanvar, {'ddof': 1}, {'ddof': 1}),
+                          ("kurtosis",  kurtosis, {}, {'bias': False, 'nan_policy': 'omit'}),
+                          ("skew",  skew, {}, {'nan_policy': 'omit'}),
+                          ("sem",  sem, {}, {'nan_policy': 'omit'})])
+def test_stat_method(pandasmethname, npfunction, kwargs, np_kwargs):
     s = pd.Series(data=[1, 2, 3, 4, 5, 6, np.nan, np.nan], dtype="Int64")
-    result = s.var(ddof=ddof)
-    expected = np.nanvar([1, 2, 3, 4, 5, 6, np.nan, np.nan], ddof=ddof)
-    assert expected == result
-
+    pandasmeth = getattr(s, pandasmethname)
+    result = pandasmeth(**kwargs)
+    expected = npfunction([1, 2, 3, 4, 5, 6, np.nan, np.nan], **np_kwargs)
+    assert np.isclose(expected, result)
 
 # TODO(jreback) - these need testing / are broken
 

From ef15fb94a415fe34d9ed3d1f68d537b6a7dd0c2b Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Tue, 5 Nov 2019 03:07:21 +0100
Subject: [PATCH 15/17] fix test

---
 pandas/tests/arrays/test_integer.py | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/pandas/tests/arrays/test_integer.py b/pandas/tests/arrays/test_integer.py
index a98142673bf56..ad84cbbeb4930 100644
--- a/pandas/tests/arrays/test_integer.py
+++ b/pandas/tests/arrays/test_integer.py
@@ -1,6 +1,5 @@
 import numpy as np
 import pytest
-from scipy.stats import kurtosis, skew, sem
 
 import pandas.util._test_decorators as td
 
@@ -830,18 +829,20 @@ def test_arrow_array(data):
     assert arr.equals(expected)
 
 
-@pytest.mark.parametrize("pandasmethname, npfunction, kwargs, np_kwargs",
-                         [("var",  np.nanvar, {'ddof': 0}, {'ddof': 0}),
-                          ("var",  np.nanvar, {'ddof': 1}, {'ddof': 1}),
-                          ("kurtosis",  kurtosis, {}, {'bias': False, 'nan_policy': 'omit'}),
-                          ("skew",  skew, {}, {'nan_policy': 'omit'}),
-                          ("sem",  sem, {}, {'nan_policy': 'omit'})])
-def test_stat_method(pandasmethname, npfunction, kwargs, np_kwargs):
+@pytest.mark.parametrize("pandasmethname, kwargs",
+                         [("var", {'ddof': 0}),
+                          ("var", {'ddof': 1}),
+                          ("kurtosis", {}),
+                          ("skew", {}),
+                          ("sem", {})])
+def test_stat_method(pandasmethname, kwargs):
     s = pd.Series(data=[1, 2, 3, 4, 5, 6, np.nan, np.nan], dtype="Int64")
     pandasmeth = getattr(s, pandasmethname)
     result = pandasmeth(**kwargs)
-    expected = npfunction([1, 2, 3, 4, 5, 6, np.nan, np.nan], **np_kwargs)
-    assert np.isclose(expected, result)
+    s2 = pd.Series(data=[1, 2, 3, 4, 5, 6], dtype="Int64")
+    pandasmeth = getattr(s2, pandasmethname)
+    expected =  pandasmeth(**kwargs)
+    assert expected == result
 
 # TODO(jreback) - these need testing / are broken
 

From 0fe89699027ef38feb7572427283516ff852fb37 Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Tue, 5 Nov 2019 09:30:43 +0100
Subject: [PATCH 16/17] minor changes

---
 pandas/tests/arrays/test_integer.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/tests/arrays/test_integer.py b/pandas/tests/arrays/test_integer.py
index ad84cbbeb4930..50a73501397d9 100644
--- a/pandas/tests/arrays/test_integer.py
+++ b/pandas/tests/arrays/test_integer.py
@@ -841,7 +841,7 @@ def test_stat_method(pandasmethname, kwargs):
     result = pandasmeth(**kwargs)
     s2 = pd.Series(data=[1, 2, 3, 4, 5, 6], dtype="Int64")
     pandasmeth = getattr(s2, pandasmethname)
-    expected =  pandasmeth(**kwargs)
+    expected = pandasmeth(**kwargs)
     assert expected == result
 
 # TODO(jreback) - these need testing / are broken

From bc6ccc43d720aa4df6ec23da16e74bd2487c5486 Mon Sep 17 00:00:00 2001
From: Moi <moi@localhost.localdomain>
Date: Tue, 5 Nov 2019 10:02:23 +0100
Subject: [PATCH 17/17] black pandas

---
 pandas/tests/arrays/test_integer.py | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/pandas/tests/arrays/test_integer.py b/pandas/tests/arrays/test_integer.py
index 50a73501397d9..025366e5b210b 100644
--- a/pandas/tests/arrays/test_integer.py
+++ b/pandas/tests/arrays/test_integer.py
@@ -829,12 +829,16 @@ def test_arrow_array(data):
     assert arr.equals(expected)
 
 
-@pytest.mark.parametrize("pandasmethname, kwargs",
-                         [("var", {'ddof': 0}),
-                          ("var", {'ddof': 1}),
-                          ("kurtosis", {}),
-                          ("skew", {}),
-                          ("sem", {})])
+@pytest.mark.parametrize(
+    "pandasmethname, kwargs",
+    [
+        ("var", {"ddof": 0}),
+        ("var", {"ddof": 1}),
+        ("kurtosis", {}),
+        ("skew", {}),
+        ("sem", {}),
+    ],
+)
 def test_stat_method(pandasmethname, kwargs):
     s = pd.Series(data=[1, 2, 3, 4, 5, 6, np.nan, np.nan], dtype="Int64")
     pandasmeth = getattr(s, pandasmethname)
@@ -844,6 +848,7 @@ def test_stat_method(pandasmethname, kwargs):
     expected = pandasmeth(**kwargs)
     assert expected == result
 
+
 # TODO(jreback) - these need testing / are broken
 
 # shift