Fix type annotation for pandas.core.generic.py (#25909)

Author: vaibhavhrt

mypy.ini

@@ -59,12 +59,6 @@ ignore_errors=True
 [mypy-pandas.core.config_init]
 ignore_errors=True
 
-[mypy-pandas.core.frame]
-ignore_errors=True
-
-[mypy-pandas.core.generic]
-ignore_errors=True
-
 [mypy-pandas.core.groupby.generic]
 ignore_errors=True
 

pandas/core/frame.py

@@ -16,7 +16,7 @@
 import sys
 import warnings
 from textwrap import dedent
-from typing import List, Optional, Union
+from typing import FrozenSet, List, Optional, Set, Type, Union
 
 import numpy as np
 import numpy.ma as ma
@@ -360,10 +360,11 @@ class DataFrame(NDFrame):
     def _constructor(self):
         return DataFrame
 
-    _constructor_sliced = Series
-    _deprecations = NDFrame._deprecations | frozenset(
-        ['get_value', 'set_value', 'from_csv', 'from_items'])
-    _accessors = set()
+    _constructor_sliced = Series  # type: Type[Series]
+    _deprecations = NDFrame._deprecations | frozenset([
+        'get_value', 'set_value', 'from_csv', 'from_items'
+    ])  # type: FrozenSet[str]
+    _accessors = set()  # type: Set[str]
 
     @property
     def _constructor_expanddim(self):

pandas/core/generic.py

@@ -6,6 +6,7 @@
 import operator
 import pickle
 from textwrap import dedent
+from typing import FrozenSet, List, Set
 import warnings
 import weakref
 
@@ -108,12 +109,13 @@ class NDFrame(PandasObject, SelectionMixin):
     _internal_names = ['_data', '_cacher', '_item_cache', '_cache', '_is_copy',
                        '_subtyp', '_name', '_index', '_default_kind',
                        '_default_fill_value', '_metadata', '__array_struct__',
-                       '__array_interface__']
-    _internal_names_set = set(_internal_names)
-    _accessors = frozenset()
-    _deprecations = frozenset(['as_blocks', 'blocks',
-                               'convert_objects', 'is_copy'])
-    _metadata = []
+                       '__array_interface__']  # type: List[str]
+    _internal_names_set = set(_internal_names)  # type: Set[str]
+    _accessors = set()  # type: Set[str]
+    _deprecations = frozenset([
+        'as_blocks', 'blocks', 'convert_objects', 'is_copy'
+    ])  # type: FrozenSet[str]
+    _metadata = []  # type: List[str]
     _is_copy = None
 
     # ----------------------------------------------------------------------