Removed mutated from public interface

Author: topper-123

doc/source/whatsnew/v1.0.0.rst

@@ -215,8 +215,7 @@ Deprecations
   value in ``idx`` of ``idx_val`` and a new value of ``val``, ``idx.set_value(arr, idx_val, val)``
   is equivalent to ``arr[idx.get_loc(idx_val)] = val``, which should be used instead (:issue:`28621`).
 - :func:`is_extension_type` is deprecated, :func:`is_extension_array_dtype` should be used instead (:issue:`29457`)
-- :meth:`DataFrame.groupby` and :meth:`Series.groupby` accepted a ``mutated`` parameter, which is actually
-  an implementation detail. It has been deprecated in the public interface (:issue:`29511`).
+
 
 .. _whatsnew_1000.prior_deprecations:
 

pandas/core/generic.py

@@ -7830,7 +7830,6 @@ def groupby(
         group_keys=True,
         squeeze=False,
         observed=False,
-        mutated=False,
     ):
         """
         Group DataFrame or Series using a mapper or by a Series of columns.
@@ -7875,10 +7874,6 @@ def groupby(
             If False: show all values for categorical groupers.
 
             .. versionadded:: 0.23.0
-        mutated : bool, default False
-            .. deprecated:: 1.0
-               This is an internal parameter and will be removed from the public
-               interface in the future
 
         Returns
         -------
@@ -7947,11 +7942,6 @@ def groupby(
             raise TypeError("You have to supply one of 'by' and 'level'")
         axis = self._get_axis_number(axis)
 
-        if mutated is not False:
-            warnings.warn(
-                "Parameter 'mutated' is deprecated", FutureWarning, stacklevel=2
-            )
-
         return get_groupby(
             self,
             by=by,
@@ -7962,7 +7952,6 @@ def groupby(
             group_keys=group_keys,
             squeeze=squeeze,
             observed=observed,
-            mutated=mutated,
         )
 
     def asfreq(self, freq, method=None, how=None, normalize=False, fill_value=None):

pandas/core/groupby/groupby.py

@@ -2501,11 +2501,16 @@ def get_groupby(
     observed: bool = False,
     mutated: bool = False,
 ):
-    from pandas.core.groupby.generic import DataFrameGroupBy, SeriesGroupBy
 
     if isinstance(obj, Series):
-        klass = SeriesGroupBy
+        from pandas.core.groupby.generic import SeriesGroupBy
+
+        klass = (
+            SeriesGroupBy
+        )  # type: Union[Type["SeriesGroupBy"], Type["DataFrameGroupBy"]]
     elif isinstance(obj, DataFrame):
+        from pandas.core.groupby.generic import DataFrameGroupBy
+
         klass = DataFrameGroupBy
     else:
         raise TypeError("invalid type: {obj}".format(obj=obj))

pandas/tests/groupby/test_groupby.py

@@ -953,13 +953,6 @@ def test_no_mutate_but_looks_like():
     tm.assert_series_equal(result1, result2)
 
 
-def test_mutated_deprecated():
-    # GH-29511
-    df = DataFrame({"key": [1, 1, 1, 2, 2, 2, 3, 3, 3], "value": range(9)})
-    with tm.assert_produces_warning(FutureWarning, check_stacklevel=True):
-        df.groupby("key", mutated=True)
-
-
 def test_groupby_series_indexed_differently():
     s1 = Series(
         [5.0, -9.0, 4.0, 100.0, -5.0, 55.0, 6.7],