diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 1b004b1f3..2958c9173 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -18,7 +18,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13-dev"]
+        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]
         architecture: ["x64", "x86"]
 
     steps:
@@ -53,7 +53,7 @@ jobs:
       - name: Run tests
         # Run the tests directly from the source dir so support files (eg, .wav files etc)
         # can be found - they aren't installed into the Python tree.
-        run: python pywin32_testall.py -v -skip-adodbapi
+        run: python -X dev pywin32_testall.py -v -skip-adodbapi
 
       - name: Build wheels
         run: |
@@ -76,7 +76,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.10", "3.11", "3.12", "3.13-dev"]
+        python-version: ["3.10", "3.11", "3.12", "3.13"]
     steps:
       - uses: actions/checkout@v4
 
@@ -118,7 +118,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           # This job only needs to target the oldest supported version
-          python-version: "3.8"
+          python-version: "3.9"
           cache: pip
           cache-dependency-path: .github/workflows/main.yml
       - run: pip install clang-format pycln
@@ -140,8 +140,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        # mypy won't understand "3.13-dev", keeping the CI simple by just omitting it
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
@@ -159,7 +158,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13-dev"]
+        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
diff --git a/Pythonwin/pywin/framework/app.py b/Pythonwin/pywin/framework/app.py
index 4b19a5b71..bfcd11155 100644
--- a/Pythonwin/pywin/framework/app.py
+++ b/Pythonwin/pywin/framework/app.py
@@ -10,7 +10,7 @@
 import os
 import sys
 import traceback
-from typing import TYPE_CHECKING
+from typing import Literal
 
 import regutil
 import win32api
@@ -21,9 +21,6 @@
 
 from . import scriptutils
 
-if TYPE_CHECKING:
-    from typing_extensions import Literal
-
 
 # Helper for writing a Window position by name, and later loading it.
 def SaveWindowSize(section, rect, state=""):
diff --git a/Pythonwin/pywin/framework/intpyapp.py b/Pythonwin/pywin/framework/intpyapp.py
index de02fdace..05244b4cc 100644
--- a/Pythonwin/pywin/framework/intpyapp.py
+++ b/Pythonwin/pywin/framework/intpyapp.py
@@ -3,6 +3,7 @@
 import os
 import sys
 import traceback
+from collections.abc import Sequence
 
 import __main__
 import commctrl
@@ -268,7 +269,7 @@ def Activate(self):
         if frame.GetWindowPlacement()[1] == win32con.SW_SHOWMINIMIZED:
             frame.ShowWindow(win32con.SW_RESTORE)
 
-    def ProcessArgs(self, args, dde=None):
+    def ProcessArgs(self, args: Sequence[str], dde=None):
         # If we are going to talk to a remote app via DDE, then
         # activate it!
         if (
@@ -290,7 +291,7 @@ def ProcessArgs(self, args, dde=None):
                 ).lower()
                 i -= 1  #  arg is /edit's parameter
             par = i < len(args) and args[i] or "MISSING"
-            if argType in ("/nodde", "/new", "-nodde", "-new"):
+            if argType in ("/nodde", "/new"):
                 # Already handled
                 pass
             elif argType.startswith("/goto:"):
diff --git a/Pythonwin/pywin/idle/CallTips.py b/Pythonwin/pywin/idle/CallTips.py
index c15847955..21b16de53 100644
--- a/Pythonwin/pywin/idle/CallTips.py
+++ b/Pythonwin/pywin/idle/CallTips.py
@@ -94,10 +94,8 @@ def get_object_at_cursor(
             # How is this for a hack!
             import __main__
 
-            namespace = sys.modules.copy()
-            namespace.update(__main__.__dict__)
             try:
-                return eval(word, namespace)
+                return eval(word, sys.modules | __main__.__dict__)
             except:
                 pass
         return None  # Can't find an object.
diff --git a/Pythonwin/pywin/scintilla/view.py b/Pythonwin/pywin/scintilla/view.py
index 0134f3151..b4da1146a 100644
--- a/Pythonwin/pywin/scintilla/view.py
+++ b/Pythonwin/pywin/scintilla/view.py
@@ -480,7 +480,7 @@ def list2dict(l):
                 # extra attributes of win32ui objects
                 if hasattr(ob, "_obj_"):
                     try:
-                        items_dict.update(list2dict(dir(ob._obj_)))
+                        items_dict = list2dict(dir(ob._obj_))
                     except AttributeError:
                         pass  # object has no __dict__
 
@@ -650,8 +650,7 @@ def _GetObjectAtPos(self, pos=-1, bAllowCalls=0):
         left, right = self._GetWordSplit(pos, bAllowCalls)
         if left:  # It is an attribute lookup
             # How is this for a hack!
-            namespace = sys.modules.copy()
-            namespace.update(__main__.__dict__)
+            namespace = sys.modules | __main__.__dict__
             # Get the debugger's context.
             try:
                 from pywin.framework import interact
diff --git a/Pythonwin/pywin/test/test_pywin.py b/Pythonwin/pywin/test/test_pywin.py
index 49acc9d5e..b2802795f 100644
--- a/Pythonwin/pywin/test/test_pywin.py
+++ b/Pythonwin/pywin/test/test_pywin.py
@@ -139,9 +139,13 @@ def t_Browse(*args):
         if __name__ != "__main__":
             # make T findable by browser in __main__ namespace
             setattr(__main__, __class__.__qualname__, __class__)
-        with mock.patch(
-            "pywin.mfc.dialog.GetSimpleInput", (lambda *args: __class__.__qualname__)
-        ), mock.patch("pywin.tools.browser.Browse", t_Browse):
+        with (
+            mock.patch(
+                "pywin.mfc.dialog.GetSimpleInput",
+                (lambda *args: __class__.__qualname__),
+            ),
+            mock.patch("pywin.tools.browser.Browse", t_Browse),
+        ):
             self.app.OnViewBrowse(0, 0)
         hl = o.dlg.hier_list
         self.assertGreater(len(hl.itemHandleMap), 10)
@@ -443,8 +447,9 @@ def t_brk(self):
             GUIAboutToBreak()
 
         dmod = types.ModuleType("__main__", "debugger test main")
-        with mock.patch("pywin.framework.scriptutils.__main__", dmod), mock.patch(
-            "pywin.debugger.debugger.Debugger.GUIAboutToBreak", t_brk
+        with (
+            mock.patch("pywin.framework.scriptutils.__main__", dmod),
+            mock.patch("pywin.debugger.debugger.Debugger.GUIAboutToBreak", t_brk),
         ):
             mf.SendMessage(wc.WM_COMMAND, cmGo)  # debh.OnGo(0, 0)
         self.assertFalse(cmds_brk_next, "break commands remaining")
diff --git a/Pythonwin/win32cmdui.cpp b/Pythonwin/win32cmdui.cpp
index 617c8e5f6..247314652 100644
--- a/Pythonwin/win32cmdui.cpp
+++ b/Pythonwin/win32cmdui.cpp
@@ -27,19 +27,6 @@ inline void *GetPythonOleProcAddress(const char *procName)
 #endif
     hMod = GetModuleHandle(buf);
 
-    // XXX It is unclear why the code previously tried to identify a loaded PythonCOM DLL of
-    // any Python version 1.5 .. 3.9. If some InprocServer would load the DLL of a different
-    // Python version that would likely cause a crash. Thus deactivated.
-    //
-    //     for (int i = 0; hMod == NULL && i < 40; i++) {
-    // #ifdef _DEBUG
-    //         wsprintf(buf, _T("PythonCOM3%d_d.dll"), i);
-    // #else
-    //         wsprintf(buf, _T("PythonCOM3%d.dll"), i);
-    // #endif
-    //         hMod = GetModuleHandle(buf);
-    //     }
-
     if (hMod) {
         void *rc = GetProcAddress(hMod, procName);
         if (rc == NULL)
diff --git a/Pythonwin/win32uimodule.cpp b/Pythonwin/win32uimodule.cpp
index e5e03878f..c9a0a214d 100644
--- a/Pythonwin/win32uimodule.cpp
+++ b/Pythonwin/win32uimodule.cpp
@@ -2559,9 +2559,9 @@ extern "C" PYW_EXPORT BOOL Win32uiApplicationInit(Win32uiHostGlue *pGlue, const
     PyObject *argv = PySys_GetObject("argv");
     PyInit_win32ui();
     // Decide if we render sys.argv from command line.
-    // PY3.6- Py_Initialize sets sys.argv=NULL .
-    // PY3.7 Py_Initialize or intentional script triggers set sys.argv=[] .
-    // PY3.8+ Py_Initialize sets sys.argv=[''] - cannot be distinguished
+    // Python 3.6- Py_Initialize sets sys.argv=NULL .
+    // Python 3.7 Py_Initialize or intentional script triggers set sys.argv=[] .
+    // Python 3.8+ Py_Initialize sets sys.argv=[''] - cannot be distinguished
     //   from a pre-existing command line setup anymore. So we need to check
     //   another flag regarding the intended type of invokation, e.g. `cmd`
     //   (or untangle all that crossover startup + module + app init here)
diff --git a/build_all.bat b/build_all.bat
index ec8cbbaa2..2260a6682 100644
--- a/build_all.bat
+++ b/build_all.bat
@@ -1,7 +1,3 @@
-py -3.8-32 setup.py -q build
-@if errorlevel 1 goto failed
-py -3.8 setup.py -q build
-@if errorlevel 1 goto failed
 py -3.9-32 setup.py -q build
 @if errorlevel 1 goto failed
 py -3.9 setup.py -q build
diff --git a/build_env.md b/build_env.md
index 7e166c4d9..61443b3fa 100644
--- a/build_env.md
+++ b/build_env.md
@@ -5,7 +5,7 @@ This describes how to setup the build environment for pywin32.
 Double check the compiler version you need in the [Python wiki](https://wiki.python.org/moin/WindowsCompilers)
 but note that Python 3.5 -> 3.13 all use version 14.X of the compiler, which,
 confusingly, report themselves as V.19XX (eg, note in Python's banner,
-3.5's "MSC v.1900", even 3.9b4's "MSC v.1924")
+3.5's "MSC v.1900", even 3.13's "MSC v.1941")
 
 This compiler first shipped with Visual Studio 2015, although Visual Studio
 2017, 2019 and 2022 all have this compiler available, just not installed
diff --git a/com/win32com/client/gencache.py b/com/win32com/client/gencache.py
index 717f2a9c7..c445c38c6 100644
--- a/com/win32com/client/gencache.py
+++ b/com/win32com/client/gencache.py
@@ -97,6 +97,7 @@ def _LoadDicts():
         arc_path = loader.archive
         dicts_path = os.path.join(win32com.__gen_path__, "dicts.dat")
         if dicts_path.startswith(arc_path):
+            # Remove the leading slash as well
             dicts_path = dicts_path[len(arc_path) + 1 :]
         else:
             # Hm. See below.
diff --git a/isapi/install.py b/isapi/install.py
index aa861bbfc..c4c61fb76 100644
--- a/isapi/install.py
+++ b/isapi/install.py
@@ -626,7 +626,7 @@ def _PatchParamsModule(params, dll_name, file_must_exist=True):
                 sm.Module = dll_name
 
 
-def GetLoaderModuleName(mod_name, check_module=None):
+def GetLoaderModuleName(mod_name: str, check_module=None):
     # find the name of the DLL hosting us.
     # By default, this is "_{module_base_name}.dll"
     if hasattr(sys, "frozen"):
@@ -635,8 +635,7 @@ def GetLoaderModuleName(mod_name, check_module=None):
         base, ext = os.path.splitext(mod_name)
         path, base = os.path.split(base)
         # handle the common case of 'foo.exe'/'foow.exe'
-        if base.endswith("w"):
-            base = base[:-1]
+        base.removesuffix("w")
         # For py2exe, we have '_foo.dll' as the standard pyisapi loader - but
         # 'foo.dll' is what we use (it just delegates).
         # So no leading '_' on the installed name.
@@ -760,8 +759,7 @@ def HandleCommandLine(
 
     # build a usage string if we don't have one.
     if not parser.get_usage():
-        all_handlers = standard_arguments.copy()
-        all_handlers.update(custom_arg_handlers)
+        all_handlers = standard_arguments | custom_arg_handlers
         parser.set_usage(build_usage(all_handlers))
 
     # allow the user to use uninstall as a synonym for remove if it wasn't
diff --git a/make_all.bat b/make_all.bat
index 05855ddfb..433a79545 100644
--- a/make_all.bat
+++ b/make_all.bat
@@ -13,11 +13,6 @@ rem Now the binaries.
 rem Check /build_env.md#build-environment to make sure you have all the required components installed
 
 rem (bdist_wininst needs --target-version to name the installers correctly!)
-py -3.8-32 setup.py -q bdist_wininst --skip-build --target-version=3.8
-py -3.8-32 setup.py -q bdist_wheel --skip-build
-py -3.8 setup.py -q bdist_wininst --skip-build --target-version=3.8
-py -3.8 setup.py -q bdist_wheel --skip-build
-
 py -3.9-32 setup.py -q bdist_wininst --skip-build --target-version=3.9
 py -3.9-32 setup.py -q bdist_wheel --skip-build
 py -3.9 setup.py -q bdist_wininst --skip-build --target-version=3.9
diff --git a/mypy.ini b/mypy.ini
index e4676e0c7..4a70beb4e 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -1,7 +1,7 @@
 [mypy]
 show_column_numbers = true
 ; Target the oldest supported version in editors and default CLI
-python_version = 3.8
+python_version = 3.9
 
 strict = true
 implicit_reexport = true
diff --git a/pyrightconfig.json b/pyrightconfig.json
index c35e4a565..87fddbc9c 100644
--- a/pyrightconfig.json
+++ b/pyrightconfig.json
@@ -1,12 +1,12 @@
 {
   "typeCheckingMode": "basic",
   // Target the oldest supported version in editors and default CLI
-  "pythonVersion": "3.8",
+  "pythonVersion": "3.9",
   // Keep it simple for now by allowing both mypy and pyright to use `type: ignore`
   "enableTypeIgnoreComments": true,
   // Exclude from scanning when running pyright
   "exclude": [
-    ".git/",
+    ".git/", // Avoids scanning git branch names ending in ".py"
     "build/",
     // Vendored
     "Pythonwin/Scintilla/",
@@ -38,7 +38,7 @@
   "reportOptionalIterable": "warning",
   "reportOptionalMemberAccess": "warning",
   "reportOptionalSubscript": "warning",
-  // Needs fixes in types-pywin32 and requires Python 3.8 to annotate ambiguous global variables
+  // Needs fixes in types-pywin32 to annotate ambiguous global variables
   "reportUnnecessaryComparison": "warning",
   // Too many dynamically generated modules. This will require type stubs to properly fix.
   "reportMissingImports": "warning",
diff --git a/ruff.toml b/ruff.toml
index 315a9d41f..199733005 100644
--- a/ruff.toml
+++ b/ruff.toml
@@ -1,4 +1,4 @@
-target-version = "py38" # Target the oldest supported version in editors and default CLI
+target-version = "py39" # Target the oldest supported version in editors and default CLI
 # This file is not UTF-8
 extend-exclude = ["Pythonwin/pywin/test/_dbgscript.py"]
 
@@ -16,12 +16,7 @@ select = [
   # String formatting, concatenating, interpolation, ...
   "FLY", # static-join-to-f-string
   "G", # flake8-logging-format
-  # Note, we still want to allow multiline ISC
-  "UP025", # Remove unicode literals from strings
-  "UP030", # Use implicit references for positional format fields
-  # TODO: Still lots of manual fixes needed
-  # "UP031", # Use format specifiers instead of percent format
-  # "UP032", # Use f-string instead of format call
+  "UP", # pyupgrade
 
   # Ensure modern type annotation syntax and best practices
   # Not including those covered by type-checkers
@@ -31,21 +26,38 @@ select = [
   "UP006", # non-pep585-annotation
   "UP007", # non-pep604-annotation
   "UP010", # unnecessary-future-import
+  "UP035", # deprecated-import
   "UP037", # quoted-annotation
 
   # Helps prevent circular imports and other unneeded imports
   "TCH", # flake8-type-checking
 ]
 extend-ignore = [
+  # We prefer explicit open mode parameter
+  "UP015", # redundant-open-modes
   # No such concerns for stdlib
   "TCH003", # typing-only-standard-library-import
+  # TODO: Still lots of manual fixes needed
+  "UP031", # Use format specifiers instead of percent format
+  "UP032", # Use f-string instead of format call
 ]
 
 [lint.per-file-ignores]
 # Explicit re-exports is fine in __init__.py, still a code smell elsewhere.
 "__init__.py" = ["PLC0414"]
 # TODO: Make adodbapi changes in their own PRs
-"adodbapi/*" = ["C4", "YTT301", "UP031", "UP032"]
+"adodbapi/*" = [
+  "C4",
+  "UP031",
+  "UP032",
+  # Dropping Python 3.8 support
+  "UP005",
+  "UP006",
+  "UP018",
+  "UP035",
+  "UP036",
+  "YTT301",
+]
 
 [lint.isort]
 combine-as-imports = true
diff --git a/setup.py b/setup.py
index bd63dead1..6b448af6e 100644
--- a/setup.py
+++ b/setup.py
@@ -34,6 +34,7 @@
 import subprocess
 import sys
 import winreg
+from collections.abc import Iterable
 from pathlib import Path
 from setuptools import Extension, setup
 from setuptools.command.build import build
@@ -42,7 +43,6 @@
 from setuptools.command.install_lib import install_lib
 from setuptools.modified import newer_group
 from tempfile import gettempdir
-from typing import Iterable
 
 from distutils import ccompiler
 from distutils._msvccompiler import MSVCCompiler
@@ -381,7 +381,7 @@ def _why_cant_build_extension(self, ext):
         # axdebug fails to build on 3.11 due to Python "frame" objects changing.
         # This could be fixed, but is almost certainly not in use any more, so
         # just skip it.
-        if ext.name == "axdebug" and sys.version_info > (3, 10):
+        if ext.name == "axdebug" and sys.version_info >= (3, 11):
             return "AXDebug no longer builds on 3.11 and up"
 
         include_dirs = self.compiler.include_dirs + os.environ.get("INCLUDE", "").split(
@@ -896,8 +896,8 @@ def install(self):
         # This is crazy - in setuptools 61.1.0 (and probably some earlier versions), the
         # install_lib and build comments don't agree on where the .py files to install can
         # be found, so we end up with a warning logged:
-        # `warning: my_install_lib: 'build\lib.win-amd64-3.8' does not exist -- no Python modules to install`
-        # (because they are actually in `build\lib.win-amd64-cpython-38`!)
+        # `warning: my_install_lib: 'build\lib.win-amd64-3.XX' does not exist -- no Python modules to install`
+        # (because they are actually in `build\lib.win-amd64-cpython-3XX`!)
         # It's not an error though, so we end up with .exe installers lacking our lib files!
         builder = self.get_finalized_command("build")
         if os.path.isdir(builder.build_platlib) and not os.path.isdir(self.build_dir):
@@ -934,7 +934,7 @@ def link(
         debug=0,
         *args,
         **kw,
-    ):
+    ) -> None:
         super().link(
             target_desc,
             objects,
@@ -952,18 +952,18 @@ def link(
         # target.  Do this externally to avoid suddenly dragging in the
         # modules needed by this process, and which we will soon try and
         # update.
-        args = [
-            sys.executable,
-            # NOTE: On Python 3.7, all args must be str
-            str(Path(__file__).parent / "win32" / "Lib" / "win32verstamp.py"),
-            f"--version={pywin32_version}",
-            "--comments=https://github.com/mhammond/pywin32",
-            f"--original-filename={os.path.basename(output_filename)}",
-            "--product=PyWin32",
-            "--quiet" if "-v" not in sys.argv else "",
-            output_filename,
-        ]
-        self.spawn(args)
+        self.spawn(
+            [
+                sys.executable,
+                str(Path(__file__).parent / "win32" / "Lib" / "win32verstamp.py"),
+                f"--version={pywin32_version}",
+                "--comments=https://github.com/mhammond/pywin32",
+                f"--original-filename={os.path.basename(output_filename)}",
+                "--product=PyWin32",
+                "--quiet" if "-v" not in sys.argv else "",
+                output_filename,
+            ]
+        )
 
     # Work around bpo-36302/bpo-42009 - it sorts sources but this breaks
     # support for building .mc files etc :(
@@ -2017,9 +2017,7 @@ def convert_data_files(files: Iterable[str]):
                 raise RuntimeError("No file '%s'" % file)
             files_use = (file,)
         for fname in files_use:
-            path_use = os.path.dirname(fname)
-            if path_use.startswith("com\\"):
-                path_use = path_use[4:]
+            path_use = os.path.dirname(fname).removeprefix("com\\")
             ret.append((path_use, (fname,)))
     return ret
 
@@ -2101,7 +2099,6 @@ def convert_optional_data_files(files):
     "Intended Audience :: Developers",
     "License :: OSI Approved :: Python Software Foundation License",
     "Operating System :: Microsoft :: Windows",
-    "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
diff --git a/win32/Demos/win32netdemo.py b/win32/Demos/win32netdemo.py
index 6c0a55776..6b8750ced 100644
--- a/win32/Demos/win32netdemo.py
+++ b/win32/Demos/win32netdemo.py
@@ -194,8 +194,7 @@ def SetInfo(userName=None):
         userName = win32api.GetUserName()
     oldData = win32net.NetUserGetInfo(server, userName, 3)
     try:
-        d = oldData.copy()
-        d["usr_comment"] = "Test comment"
+        d = oldData | {"usr_comment": "Test comment"}
         win32net.NetUserSetInfo(server, userName, 3, d)
         new = win32net.NetUserGetInfo(server, userName, 3)["usr_comment"]
         if str(new) != "Test comment":
diff --git a/win32/Lib/_win32verstamp_pywin32ctypes.py b/win32/Lib/_win32verstamp_pywin32ctypes.py
index b878809b7..33333422f 100644
--- a/win32/Lib/_win32verstamp_pywin32ctypes.py
+++ b/win32/Lib/_win32verstamp_pywin32ctypes.py
@@ -30,13 +30,12 @@
     LPVOID,
     WORD,
 )
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Literal, SupportsBytes, SupportsIndex
 
 if TYPE_CHECKING:
     from ctypes import _NamedFuncPointer
 
     from _typeshed import ReadableBuffer
-    from typing_extensions import Literal, SupportsBytes, SupportsIndex
 
 kernel32 = WinDLL("kernel32", use_last_error=True)
 
diff --git a/win32/Lib/win32timezone.py b/win32/Lib/win32timezone.py
index 01aa08d79..e7d815eda 100644
--- a/win32/Lib/win32timezone.py
+++ b/win32/Lib/win32timezone.py
@@ -246,7 +246,6 @@
 import struct
 import winreg
 from itertools import count
-from typing import Dict
 
 import win32api
 
@@ -855,7 +854,7 @@ def get_sorted_time_zones(key=None):
         return zones
 
 
-class _RegKeyDict(Dict[str, int]):
+class _RegKeyDict(dict[str, int]):
     def __init__(self, key: winreg.HKEYType):
         dict.__init__(self)
         self.key = key
diff --git a/win32/scripts/VersionStamp/bulkstamp.py b/win32/scripts/VersionStamp/bulkstamp.py
index 89be6347d..0500745bf 100644
--- a/win32/scripts/VersionStamp/bulkstamp.py
+++ b/win32/scripts/VersionStamp/bulkstamp.py
@@ -33,7 +33,7 @@
 import fnmatch
 import os
 import sys
-from collections.abc import Mapping
+from collections.abc import Iterable, Mapping
 from optparse import Values
 
 try:
@@ -51,7 +51,9 @@
 ]
 
 
-def walk(vars: Mapping[str, str], debug, descriptions, dirname, names) -> int:
+def walk(
+    vars: Mapping[str, str], debug, descriptions, dirname, names: Iterable[str]
+) -> int:
     """Returns the number of stamped files."""
     numStamped = 0
     for name in names:
@@ -60,8 +62,7 @@ def walk(vars: Mapping[str, str], debug, descriptions, dirname, names) -> int:
                 # Handle the "_d" thing.
                 pathname = os.path.join(dirname, name)
                 base, ext = os.path.splitext(name)
-                if base.endswith("_d"):
-                    name = base[:-2] + ext
+                name = base.removesuffix("_d") + ext
                 is_dll = ext.lower() != ".exe"
                 if os.path.normcase(name) in descriptions:
                     description = descriptions[os.path.normcase(name)]
diff --git a/win32/test/test_win32cred.py b/win32/test/test_win32cred.py
index 4b9fe08d7..840263bad 100644
--- a/win32/test/test_win32cred.py
+++ b/win32/test/test_win32cred.py
@@ -14,12 +14,10 @@ def setUp(self):
         }
 
     def create_dummy_cred(self):
-        cred = copy.deepcopy(self.dummy_cred)
-        cred.update(
-            {
-                "Persist": win32cred.CRED_PERSIST_SESSION,
-            }
-        )
+        cred = copy.deepcopy(self.dummy_cred) | {
+            "Persist": win32cred.CRED_PERSIST_SESSION,
+        }
+
         try:
             win32cred.CredWrite(cred, self.flags)
         except Exception as e:
diff --git a/win32/test/test_win32crypt.py b/win32/test/test_win32crypt.py
index 9360cfbe2..f6f656caa 100644
--- a/win32/test/test_win32crypt.py
+++ b/win32/test/test_win32crypt.py
@@ -2,7 +2,8 @@
 
 import contextlib
 import unittest
-from typing import Any, Iterator
+from collections.abc import Iterator
+from typing import Any
 
 import win32crypt
 from pywin32_testutil import find_test_fixture, testmain
diff --git a/win32/test/test_win32file.py b/win32/test/test_win32file.py
index 12ba8c31d..b0eee2e3b 100644
--- a/win32/test/test_win32file.py
+++ b/win32/test/test_win32file.py
@@ -556,8 +556,7 @@ class TestFindFiles(unittest.TestCase):
     def testIter(self):
         dir = os.path.join(os.getcwd(), "*")
         files = win32file.FindFilesW(dir)
-        set1 = set()
-        set1.update(files)
+        set1 = set(files)
         set2 = set()
         for file in win32file.FindFilesIterator(dir):
             set2.add(file)
diff --git a/win32/test/test_win32gui.py b/win32/test/test_win32gui.py
index bc91a7add..b71ee8ad5 100644
--- a/win32/test/test_win32gui.py
+++ b/win32/test/test_win32gui.py
@@ -102,11 +102,7 @@ def test_enumwindows(self):
         ):
             for data in self.type_data_set:
                 self.assertRaises(TypeError, win32gui.EnumWindows, func, data)
-        if sys.version_info >= (3, 10):
-            for func in (
-                self.enum_callback,
-                self.enum_callback_sle,
-            ):
+            if sys.version_info >= (3, 10):
                 self.assertRaises(
                     TypeError, win32gui.EnumWindows, func, self.enum_callback, 2.718282
                 )
@@ -136,11 +132,7 @@ def test_enumchildwindows(self):
                 self.assertRaises(
                     TypeError, win32gui.EnumChildWindows, None, func, data
                 )
-        if sys.version_info >= (3, 10):
-            for func in (
-                self.enum_callback,
-                self.enum_callback_sle,
-            ):
+            if sys.version_info >= (3, 10):
                 self.assertRaises(
                     TypeError,
                     win32gui.EnumChildWindows,
@@ -197,11 +189,7 @@ def test_enumdesktopwindows(self):
                     self.assertRaises(
                         TypeError, win32gui.EnumDesktopWindows, 0, func, data
                     )
-        if sys.version_info >= (3, 10):
-            for func in (
-                self.enum_callback,
-                self.enum_callback_sle,
-            ):
+            if sys.version_info >= (3, 10):
                 for desktop in desktops:
                     self.assertRaises(
                         TypeError, win32gui.EnumDesktopWindows, 0, func, 2.718282