CLN: PY3 String/BytesIO (#25954)

Author: mroeschke

pandas/_libs/tslibs/parsing.pyx

@@ -2,9 +2,9 @@
 """
 Parsing functions for datetime and datetime-like strings.
 """
-import sys
 import re
 import time
+from io import StringIO
 
 from cpython.datetime cimport datetime
 
@@ -13,13 +13,6 @@ import numpy as np
 
 import six
 
-# Avoid import from outside _libs
-if sys.version_info.major == 2:
-    from StringIO import StringIO
-else:
-    from io import StringIO
-
-
 # dateutil compat
 from dateutil.tz import (tzoffset,
                          tzlocal as _dateutil_tzlocal,

pandas/compat/__init__.py

@@ -39,16 +39,9 @@
 
 try:
     import __builtin__ as builtins
-    # not writeable when instantiated with string, doesn't handle unicode well
-    from cStringIO import StringIO as cStringIO
-    # always writeable
-    from StringIO import StringIO
-    BytesIO = StringIO
     import httplib
 except ImportError:
     import builtins
-    from io import StringIO, BytesIO
-    cStringIO = StringIO
     import http.client as httplib
 
 from pandas.compat.chainmap import DeepChainMap

pandas/core/computation/expr.py

@@ -3,13 +3,14 @@
 
 import ast
 from functools import partial, reduce
+from io import StringIO
 import itertools as it
 import operator
 import tokenize
 
 import numpy as np
 
-from pandas.compat import StringIO, lmap
+from pandas.compat import lmap
 
 import pandas as pd
 from pandas import compat

pandas/core/computation/scope.py

@@ -4,6 +4,7 @@
 
 import datetime
 import inspect
+from io import StringIO
 import itertools
 import pprint
 import struct
@@ -12,7 +13,7 @@
 import numpy as np
 
 from pandas._libs.tslibs import Timestamp
-from pandas.compat import DeepChainMap, StringIO
+from pandas.compat import DeepChainMap
 
 from pandas.core.base import StringMixin
 import pandas.core.computation as compu

pandas/core/frame.py

@@ -13,6 +13,7 @@
 import collections
 from collections import OrderedDict, abc
 import functools
+from io import StringIO
 import itertools
 import sys
 import warnings
@@ -33,7 +34,7 @@
                                      validate_axis_style_args)
 
 from pandas import compat
-from pandas.compat import PY36, StringIO, lmap, lzip, raise_with_traceback
+from pandas.compat import PY36, lmap, lzip, raise_with_traceback
 from pandas.compat.numpy import function as nv
 from pandas.core.dtypes.cast import (
     maybe_upcast,

pandas/core/series.py

@@ -2,6 +2,7 @@
 Data structure for 1-dimensional cross-sectional and time series data
 """
 from collections import OrderedDict, abc
+from io import StringIO
 from shutil import get_terminal_size
 from textwrap import dedent
 import warnings
@@ -12,7 +13,7 @@
 
 from pandas._libs import iNaT, index as libindex, lib, tslibs
 import pandas.compat as compat
-from pandas.compat import PY36, StringIO
+from pandas.compat import PY36
 from pandas.compat.numpy import function as nv
 from pandas.util._decorators import Appender, Substitution, deprecate
 from pandas.util._validators import validate_bool_kwarg

pandas/io/clipboards.py

@@ -1,8 +1,8 @@
 """ io on the clipboard """
+from io import StringIO
 import warnings
 
 import pandas.compat as compat
-from pandas.compat import StringIO
 
 from pandas.core.dtypes.generic import ABCDataFrame
 

pandas/io/common.py

@@ -5,6 +5,7 @@
 import csv
 import gzip
 from http.client import HTTPException  # noqa
+from io import BytesIO
 import lzma
 import mmap
 import os
@@ -16,7 +17,6 @@
 import zipfile
 
 import pandas.compat as compat
-from pandas.compat import BytesIO
 from pandas.errors import (  # noqa
     AbstractMethodError, DtypeWarning, EmptyDataError, ParserError,
     ParserWarning)
@@ -411,7 +411,7 @@ def _get_handle(path_or_buf, mode, encoding=None, compression=None,
     return f, handles
 
 
-class BytesZipFile(zipfile.ZipFile, BytesIO):
+class BytesZipFile(zipfile.ZipFile, BytesIO):  # type: ignore
     """
     Wrapper for standard library class ZipFile and allow the returned file-like
     handle to accept byte strings via `write` method.

pandas/io/formats/csvs.py

@@ -4,14 +4,14 @@
 """
 
 import csv as csvlib
+from io import StringIO
 import os
 import warnings
 from zipfile import ZipFile
 
 import numpy as np
 
 from pandas._libs import writers as libwriters
-from pandas.compat import StringIO
 
 from pandas.core.dtypes.generic import (
     ABCDatetimeIndex, ABCIndexClass, ABCMultiIndex, ABCPeriodIndex)

pandas/io/formats/format.py

@@ -5,6 +5,7 @@
 """
 
 from functools import partial
+from io import StringIO
 from shutil import get_terminal_size
 from unicodedata import east_asian_width
 
@@ -15,7 +16,7 @@
 from pandas._libs import lib
 from pandas._libs.tslib import format_array_from_datetime
 from pandas._libs.tslibs import NaT, Timedelta, Timestamp, iNaT
-from pandas.compat import StringIO, lzip
+from pandas.compat import lzip
 
 from pandas.core.dtypes.common import (
     is_categorical_dtype, is_datetime64_dtype, is_datetime64tz_dtype,