Remove C version of _concat_date_cols

Author: vnlitvinov

pandas/_libs/tslibs/src/datetime/datehelpers.c

@@ -14,7 +14,6 @@
 
 import numpy as np
 
-#from pandas._libs.datehelpers import concat_date_cols as _concat_date_cols
 from pandas._libs.lib import _concat_date_cols
 import pandas._libs.lib as lib
 import pandas._libs.ops as libops

pandas/io/parsers.py

@@ -238,7 +238,6 @@ def initialize_options(self):
         ujson_lib = pjoin(base, 'ujson', 'lib')
         self._clean_exclude = [pjoin(dt, 'np_datetime.c'),
                                pjoin(dt, 'np_datetime_strings.c'),
-                               pjoin(dt, 'datehelpers.c'),
                                pjoin(parser, 'tokenizer.c'),
                                pjoin(parser, 'io.c'),
                                pjoin(ujson_python, 'ujson.c'),
@@ -748,20 +747,6 @@ def srcpath(name=None, suffix='.pyx', subdir='src'):
 extensions.append(_move_ext)
 
 # ----------------------------------------------------------------------
-# datehelpers
-datehelpers_sources = [
-    'pandas/_libs/tslibs/src/datetime/datehelpers.c',
-    'pandas/_libs/src/parser/tokenizer.c'
-]
-datehelpers_ext = Extension('pandas._libs.datehelpers',
-                            depends=[
-                                'pandas/_libs/src/parser/tokenizer.h'
-                            ],
-                            sources=datehelpers_sources,
-                            include_dirs=['pandas/_libs/src/klib/'],
-                            extra_compile_args=extra_compile_args,
-                            define_macros=macros)
-extensions.append(datehelpers_ext)
 
 
 # The build cache system does string matching below this point.