diff --git a/pycparserext/ext_c_generator.py b/pycparserext/ext_c_generator.py
index a2bc88d..dc958e3 100644
--- a/pycparserext/ext_c_generator.py
+++ b/pycparserext/ext_c_generator.py
@@ -21,7 +21,7 @@ def visit_UnaryOp(self, n):
             return "%s %s" % (n.op, operand)
 
 
-class AsmAndAttributesMixin(object):
+class AsmAndAttributesMixin:
     def visit_Asm(self, n):
         components = [
                 n.template,
@@ -120,7 +120,7 @@ def _generate_type(self, n, modifiers=None, emit_declname=True):
 
         elif typ in (c_ast.ArrayDecl, c_ast.PtrDecl, c_ast.FuncDecl, FuncDeclExt):
             return self._generate_type(
-                    n.type, modifiers + [n], emit_declname=emit_declname)
+                    n.type, [*modifiers, n], emit_declname=emit_declname)
 
         else:
             return self.visit(n)
diff --git a/pycparserext/ext_c_lexer.py b/pycparserext/ext_c_lexer.py
index 638d92a..e0c4edb 100644
--- a/pycparserext/ext_c_lexer.py
+++ b/pycparserext/ext_c_lexer.py
@@ -16,7 +16,7 @@ class GnuCLexer(CLexerBase):
             + CLexerBase.exponent_part+"))i?[FfLl]?)")
 
     @TOKEN(floating_constant)
-    def t_FLOAT_CONST(self, t):  # noqa: N802
+    def t_FLOAT_CONST(self, t):
         return t
 
     t_pppragma_ignore = " \t<>.-{}();+-*/$%@&^~!?:,0123456789="
@@ -32,7 +32,7 @@ def __init__(self, *args, **kwargs):
 
 
 class OpenCLCLexer(CLexerBase):
-    tokens = CLexerBase.tokens + ("LINECOMMENT",)
+    tokens = (*CLexerBase.tokens, "LINECOMMENT")
     states = (
             # ('comment', 'exclusive'),
             # ('preproc', 'exclusive'),
@@ -40,12 +40,12 @@ class OpenCLCLexer(CLexerBase):
             ("pppragma", "exclusive"),  # unused
             )
 
-    def t_LINECOMMENT(self, t):  # noqa: N802
+    def t_LINECOMMENT(self, t):
         r"\/\/([^\n]+)\n"
         t.lexer.lineno += t.value.count("\n")
 
     # overrides pycparser, must have same name
-    def t_PPHASH(self, t):  # noqa: N802
+    def t_PPHASH(self, t):
         r"[ \t]*\#([^\n]|\\\n)+[^\n\\]\n"
         t.lexer.lineno += t.value.count("\n")
         return t
diff --git a/pycparserext/ext_c_parser.py b/pycparserext/ext_c_parser.py
index 26de7bc..71e7d47 100644
--- a/pycparserext/ext_c_parser.py
+++ b/pycparserext/ext_c_parser.py
@@ -1,4 +1,3 @@
-from __future__ import division
 
 import pycparser.c_ast as c_ast
 import pycparser.c_parser
@@ -51,8 +50,7 @@ def children(self):
         return tuple(nodelist)
 
     def __iter__(self):
-        for child in (self.types or []):
-            yield child
+        yield from (self.types or [])
 
     attr_names = ()
 
@@ -260,7 +258,7 @@ def __iter__(self):
 
 # {{{ attributes
 
-class _AttributesMixin(object):
+class _AttributesMixin:
     def p_attributes_opt_1(self, p):
         """ attributes_opt : attribute_decl attributes_opt
         """
@@ -309,7 +307,7 @@ def p_function_specifier_attr(self, p):
 
 # {{{ asm
 
-class _AsmMixin(object):
+class _AsmMixin:
     def p_asm_opt_1(self, p):
         """ asm_opt : empty
         """
@@ -494,7 +492,7 @@ class GnuCParser(_AsmAndAttributesMixin, CParserBase):
 
     from pycparserext.ext_c_lexer import GnuCLexer as lexer_class  # noqa
 
-    initial_type_symbols = {"__builtin_va_list"}
+    initial_type_symbols = frozenset({"__builtin_va_list"})
 
     def p_function_specifier_gnu(self, p):
         """ function_specifier  : __INLINE
@@ -600,7 +598,7 @@ def p_unified_volatile_gnu(self, p):
 class OpenCLCParser(_AsmAndAttributesMixin, CParserBase):
     from pycparserext.ext_c_lexer import OpenCLCLexer as lexer_class  # noqa
 
-    INT_BIT_COUNTS = [8, 16, 32, 64]
+    INT_BIT_COUNTS = (8, 16, 32, 64)
     initial_type_symbols = (
             {
                 "%s%d" % (base_name, count)
diff --git a/test/test_pycparserext.py b/test/test_pycparserext.py
index 627d766..837543a 100644
--- a/test/test_pycparserext.py
+++ b/test/test_pycparserext.py
@@ -1,4 +1,3 @@
-from __future__ import print_function
 
 import pytest