diff --git a/pandas/_libs/parsers.pyx b/pandas/_libs/parsers.pyx
index 8187fb508291a..e4aeb7ad69792 100644
--- a/pandas/_libs/parsers.pyx
+++ b/pandas/_libs/parsers.pyx
@@ -34,6 +34,7 @@ cimport numpy as cnp
 from numpy cimport ndarray, uint8_t, uint64_t, int64_t, float64_t
 cnp.import_array()
 
+cimport pandas._libs.util as util
 from pandas._libs.util cimport UINT64_MAX, INT64_MAX, INT64_MIN
 import pandas._libs.lib as lib
 
@@ -279,18 +280,16 @@ cdef class TextReader:
 
     cdef public:
         int64_t leading_cols, table_width, skipfooter, buffer_lines
-        object allow_leading_cols
-        object delimiter, converters, delim_whitespace
+        bint allow_leading_cols, mangle_dupe_cols, memory_map, low_memory
+        bint delim_whitespace
+        object delimiter, converters
         object na_values
-        object memory_map
         object header, orig_header, names, header_start, header_end
         object index_col
-        object low_memory
         object skiprows
         object dtype
         object encoding
         object compression
-        object mangle_dupe_cols
         object usecols
         list dtype_cast_order
         set unnamed_cols
@@ -298,54 +297,44 @@ cdef class TextReader:
 
     def __cinit__(self, source,
                   delimiter=b',',
-
                   header=0,
                   header_start=0,
                   header_end=0,
                   index_col=None,
                   names=None,
-
-                  memory_map=False,
+                  bint memory_map=False,
                   tokenize_chunksize=DEFAULT_CHUNKSIZE,
-                  delim_whitespace=False,
-
+                  bint delim_whitespace=False,
                   compression=None,
-
                   converters=None,
-
-                  skipinitialspace=False,
+                  bint skipinitialspace=False,
                   escapechar=None,
-                  doublequote=True,
+                  bint doublequote=True,
                   quotechar=b'"',
                   quoting=0,
                   lineterminator=None,
-
                   encoding=None,
-
                   comment=None,
                   decimal=b'.',
                   thousands=None,
-
                   dtype=None,
                   usecols=None,
-                  error_bad_lines=True,
-                  warn_bad_lines=True,
-
-                  na_filter=True,
+                  bint error_bad_lines=True,
+                  bint warn_bad_lines=True,
+                  bint na_filter=True,
                   na_values=None,
                   na_fvalues=None,
-                  keep_default_na=True,
-
+                  bint keep_default_na=True,
                   true_values=None,
                   false_values=None,
-                  allow_leading_cols=True,
-                  low_memory=False,
+                  bint allow_leading_cols=True,
+                  bint low_memory=False,
                   skiprows=None,
                   skipfooter=0,
-                  verbose=False,
-                  mangle_dupe_cols=True,
+                  bint verbose=False,
+                  bint mangle_dupe_cols=True,
                   float_precision=None,
-                  skip_blank_lines=True):
+                  bint skip_blank_lines=True):
 
         # set encoding for native Python and C library
         if encoding is not None:
@@ -591,7 +580,7 @@ cdef class TextReader:
             self.parser.quotechar = ord(quote_char)
 
     cdef _make_skiprow_set(self):
-        if isinstance(self.skiprows, (int, np.integer)):
+        if util.is_integer_object(self.skiprows):
             parser_set_skipfirstnrows(self.parser, self.skiprows)
         elif not callable(self.skiprows):
             for i in self.skiprows:
@@ -683,15 +672,14 @@ cdef class TextReader:
         # header is now a list of lists, so field_count should use header[0]
 
         cdef:
-            Py_ssize_t i, start, field_count, passed_count, unnamed_count
+            Py_ssize_t i, start, field_count, passed_count, unnamed_count, level
             char *word
             object name, old_name
             uint64_t hr, data_line = 0
             char *errors = "strict"
             StringPath path = _string_path(self.c_encoding)
-
-        header = []
-        unnamed_cols = set()
+            list header = []
+            set unnamed_cols = set()
 
         if self.parser.header_start >= 0:
 
@@ -847,7 +835,7 @@ cdef class TextReader:
     cdef _read_low_memory(self, rows):
         cdef:
             size_t rows_read = 0
-            chunks = []
+            list chunks = []
 
         if rows is None:
             while True:
@@ -2038,12 +2026,11 @@ def _concatenate_chunks(list chunks):
     cdef:
         list names = list(chunks[0].keys())
         object name
-        list warning_columns
+        list warning_columns = []
         object warning_names
         object common_type
 
     result = {}
-    warning_columns = list()
     for name in names:
         arrs = [chunk.pop(name) for chunk in chunks]
         # Check each arr for consistent types.
@@ -2147,7 +2134,7 @@ def _maybe_encode(values):
 
 
 def sanitize_objects(ndarray[object] values, set na_values,
-                     convert_empty=True):
+                     bint convert_empty=True):
     """
     Convert specified values, including the given set na_values and empty
     strings if convert_empty is True, to np.nan.
@@ -2156,7 +2143,7 @@ def sanitize_objects(ndarray[object] values, set na_values,
     ----------
     values : ndarray[object]
     na_values : set
-    convert_empty : bool (default True)
+    convert_empty : bool, default True
     """
     cdef:
         Py_ssize_t i, n