CLN: Remove redundant definitions in pandas.compat (filter, map, range, etc.) (#25845)

Author: jschendel

pandas/_libs/parsers.pyx

@@ -698,7 +698,7 @@ cdef class TextReader:
 
             if ptr == NULL:
                 if not os.path.exists(source):
-                    raise compat.FileNotFoundError(
+                    raise FileNotFoundError(
                         ENOENT,
                         'File {source} does not exist'.format(source=source),
                         source)

pandas/compat/__init__.py

@@ -5,7 +5,7 @@
 Cross-compatible functions for Python 2 and 3.
 
 Key items to import for 2/3 compatible code:
-* iterators: range(), map(), zip(), filter(), reduce()
+* iterators: reduce()
 * lists: lrange(), lmap(), lzip(), lfilter()
 * unicode: u() [no unicode builtin in Python 3]
 * longs: long (int in Python 3)
@@ -107,19 +107,11 @@ def get_range_parameters(data):
         return data.start, data.stop, data.step
 
     # have to explicitly put builtins into the namespace
-    range = range
-    map = map
-    zip = zip
-    filter = filter
     intern = sys.intern
     reduce = functools.reduce
     long = int
     unichr = chr
 
-    # This was introduced in Python 3.3, but we don't support
-    # Python 3.x < 3.5, so checking PY3 is safe.
-    FileNotFoundError = FileNotFoundError
-
     # list-producing versions of the major Python iterating functions
     def lrange(*args, **kwargs):
         return list(range(*args, **kwargs))
@@ -148,8 +140,6 @@ def lfilter(*args, **kwargs):
     # Python 2
     _name_re = re.compile(r"[a-zA-Z_][a-zA-Z0-9_]*$")
 
-    FileNotFoundError = IOError
-
     def isidentifier(s, dotted=False):
         return bool(_name_re.match(s))
 
@@ -181,11 +171,7 @@ def get_range_parameters(data):
         return start, stop, step
 
     # import iterator versions of these functions
-    range = xrange
     intern = intern
-    zip = itertools.izip
-    filter = itertools.ifilter
-    map = itertools.imap
     reduce = reduce
     long = long
     unichr = unichr
@@ -217,7 +203,6 @@ def iterkeys(obj, **kw):
     def itervalues(obj, **kw):
         return obj.itervalues(**kw)
 
-    next = lambda it: it.next()
 else:
     def iteritems(obj, **kw):
         return iter(obj.items(**kw))
@@ -228,8 +213,6 @@ def iterkeys(obj, **kw):
     def itervalues(obj, **kw):
         return iter(obj.values(**kw))
 
-    next = next
-
 
 def bind_method(cls, name, func):
     """Bind a method to class, python 2 and python 3 compatible.
@@ -315,9 +298,6 @@ def set_function_name(f, name, cls):
             name=name)
         f.__module__ = cls.__module__
         return f
-
-    ResourceWarning = ResourceWarning
-
 else:
     string_types = basestring,
     integer_types = (int, long)
@@ -373,9 +353,6 @@ def set_function_name(f, name, cls):
         f.__name__ = name
         return f
 
-    class ResourceWarning(Warning):
-        pass
-
 string_and_binary_types = string_types + (binary_type,)
 
 

pandas/core/arrays/integer.py

@@ -5,7 +5,7 @@
 import numpy as np
 
 from pandas._libs import lib
-from pandas.compat import range, set_function_name, string_types
+from pandas.compat import set_function_name, string_types
 from pandas.util._decorators import cache_readonly
 
 from pandas.core.dtypes.base import ExtensionDtype

pandas/core/arrays/period.py

@@ -934,14 +934,14 @@ def _range_from_fields(year=None, month=None, quarter=None, day=None,
                 raise AssertionError("base must equal FR_QTR")
 
         year, quarter = _make_field_arrays(year, quarter)
-        for y, q in compat.zip(year, quarter):
+        for y, q in zip(year, quarter):
             y, m = libperiod.quarter_to_myear(y, q, freq)
             val = libperiod.period_ordinal(y, m, 1, 1, 1, 1, 0, 0, base)
             ordinals.append(val)
     else:
         base, mult = libfrequencies.get_freq_code(freq)
         arrays = _make_field_arrays(year, month, day, hour, minute, second)
-        for y, mth, d, h, mn, s in compat.zip(*arrays):
+        for y, mth, d, h, mn, s in zip(*arrays):
             ordinals.append(libperiod.period_ordinal(
                 y, mth, d, h, mn, s, 0, 0, base))
 

pandas/core/base.py

@@ -9,7 +9,7 @@
 
 import pandas._libs.lib as lib
 import pandas.compat as compat
-from pandas.compat import PYPY, builtins, map, range
+from pandas.compat import PYPY, builtins
 from pandas.compat.numpy import function as nv
 from pandas.errors import AbstractMethodError
 from pandas.util._decorators import Appender, Substitution, cache_readonly

pandas/core/computation/align.py

@@ -6,7 +6,6 @@
 
 import numpy as np
 
-from pandas.compat import range, zip
 from pandas.errors import PerformanceWarning
 
 import pandas as pd

pandas/core/computation/engines.py

@@ -4,8 +4,6 @@
 
 import abc
 
-from pandas.compat import map
-
 from pandas import compat
 from pandas.core.computation.align import _align, _reconstruct_object
 from pandas.core.computation.ops import (

pandas/core/computation/expr.py

@@ -9,7 +9,7 @@
 
 import numpy as np
 
-from pandas.compat import StringIO, lmap, map, reduce, string_types, zip
+from pandas.compat import StringIO, lmap, reduce, string_types
 
 import pandas as pd
 from pandas import compat

pandas/core/computation/scope.py

@@ -12,7 +12,7 @@
 import numpy as np
 
 from pandas._libs.tslibs import Timestamp
-from pandas.compat import DeepChainMap, StringIO, map
+from pandas.compat import DeepChainMap, StringIO
 
 from pandas.core.base import StringMixin
 import pandas.core.computation as compu

pandas/core/frame.py

@@ -33,9 +33,9 @@
                                      validate_axis_style_args)
 
 from pandas import compat
-from pandas.compat import (range, map, zip, lmap, lzip, StringIO, u,
-                           PY36, raise_with_traceback, Iterator,
-                           string_and_binary_types)
+from pandas.compat import (
+    PY36, Iterator, StringIO, lmap, lzip, raise_with_traceback,
+    string_and_binary_types, u)
 from pandas.compat.numpy import function as nv
 from pandas.core.dtypes.cast import (
     maybe_upcast,