CLN: remove compat.iterkeys (#26081)

* CLN: remove compat.iterkeys

* minor clean-up

Author: topper-123

pandas/compat/__init__.py

@@ -6,7 +6,7 @@
 
 Key items to import for compatible code:
 * lists: lrange(), lmap(), lzip(), lfilter()
-* iterable method compatibility: iterkeys, itervalues
+* iterable method compatibility: itervalues
   * Uses the original method if available, otherwise uses items, keys, values.
 * add_metaclass(metaclass) - class decorator that recreates class with with the
   given metaclass instead (and avoids intermediary class creation)
@@ -41,10 +41,6 @@ def lfilter(*args, **kwargs):
     return list(filter(*args, **kwargs))
 
 
-def iterkeys(obj, **kw):
-    return iter(obj.keys(**kw))
-
-
 def itervalues(obj, **kw):
     return iter(obj.values(**kw))
 

pandas/core/base.py

@@ -401,7 +401,7 @@ def nested_renaming_depr(level=4):
             else:
                 # deprecation of renaming keys
                 # GH 15931
-                keys = list(compat.iterkeys(arg))
+                keys = list(arg.keys())
                 if (isinstance(obj, ABCDataFrame) and
                         len(obj.columns.intersection(keys)) != len(keys)):
                     nested_renaming_depr()
@@ -437,7 +437,7 @@ def _agg(arg, func):
                 return result
 
             # set the final keys
-            keys = list(compat.iterkeys(arg))
+            keys = list(arg.keys())
             result = OrderedDict()
 
             # nested renamer
@@ -449,7 +449,7 @@ def _agg(arg, func):
                     result, results = OrderedDict(), result
                     for r in results:
                         result.update(r)
-                    keys = list(compat.iterkeys(result))
+                    keys = list(result.keys())
 
                 else:
 

pandas/io/stata.py

@@ -30,8 +30,8 @@
     ensure_object, is_categorical_dtype, is_datetime64_dtype)
 
 from pandas import (
-    Categorical, DatetimeIndex, NaT, Timestamp, compat, concat, isna,
-    to_datetime, to_timedelta)
+    Categorical, DatetimeIndex, NaT, Timestamp, concat, isna, to_datetime,
+    to_timedelta)
 from pandas.core.base import StringMixin
 from pandas.core.frame import DataFrame
 from pandas.core.series import Series
@@ -1700,7 +1700,7 @@ def _do_convert_categoricals(self, data, value_label_dict, lbllist,
         """
         Converts categorical columns to Categorical type.
         """
-        value_labels = list(compat.iterkeys(value_label_dict))
+        value_labels = list(value_label_dict.keys())
         cat_converted_data = []
         for col, label in zip(data, lbllist):
             if label in value_labels:

pandas/tests/io/test_stata.py

@@ -11,8 +11,6 @@
 import numpy as np
 import pytest
 
-from pandas.compat import iterkeys
-
 from pandas.core.dtypes.common import is_categorical_dtype
 
 import pandas as pd
@@ -755,8 +753,7 @@ def test_missing_value_generator(self):
     def test_missing_value_conversion(self, file):
         columns = ['int8_', 'int16_', 'int32_', 'float32_', 'float64_']
         smv = StataMissingValue(101)
-        keys = [key for key in iterkeys(smv.MISSING_VALUES)]
-        keys.sort()
+        keys = sorted(smv.MISSING_VALUES.keys())
         data = []
         for i in range(27):
             row = [StataMissingValue(keys[i + (j * 27)]) for j in range(5)]

pandas/tests/test_compat.py

@@ -5,8 +5,7 @@
 import builtins
 import re
 
-from pandas.compat import (
-    iterkeys, itervalues, lfilter, lmap, lrange, lzip, re_type)
+from pandas.compat import itervalues, lfilter, lmap, lrange, lzip, re_type
 
 
 class TestBuiltinIterators(object):
@@ -53,7 +52,6 @@ def test_lzip(self):
 
     def test_dict_iterators(self):
         assert next(itervalues({1: 2})) == 2
-        assert next(iterkeys({1: 2})) == 1
 
 
 def test_re_type():