diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 00000000..2390d8c8
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,10 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "monthly"
+    groups:
+      github-actions:
+        patterns:
+          - "*"
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index bd06d11d..186199a5 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -31,11 +31,11 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v3
+      uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v2
+      uses: github/codeql-action/init@1500a131381b66de0c52ac28abb13cd79f4b7ecc # v2.22.12
       with:
         languages: ${{ matrix.language }}
         # If you wish to specify custom queries, you can do so here or in a config file.
@@ -47,9 +47,9 @@ jobs:
 
     # Autobuild attempts to build any compiled languages (C/C++, C#, Go, Java, or Swift).
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v2
+      uses: github/codeql-action/autobuild@1500a131381b66de0c52ac28abb13cd79f4b7ecc # v2.22.12
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v2
+      uses: github/codeql-action/analyze@1500a131381b66de0c52ac28abb13cd79f4b7ecc # v2.22.12
       with:
         category: "/language:${{matrix.language}}"
diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index 53bca63b..50cfb956 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -20,9 +20,9 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0
 
-      - uses: actions/setup-python@v4
+      - uses: actions/setup-python@65d7f2d534ac1bc67fcd62888c5f4f3d2cb2b236 # v4.7.1
         name: Install Python
         with:
           python-version: "3.9"
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 712704c1..652a2f92 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -22,9 +22,9 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0
 
-      - uses: actions/setup-python@v4
+      - uses: actions/setup-python@65d7f2d534ac1bc67fcd62888c5f4f3d2cb2b236 # v4.7.1
         name: Install Python
         with:
           python-version: "3.9"
@@ -43,13 +43,13 @@ jobs:
     needs: lint
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0
 
       - name: Build
         run: pipx run build
 
       - name: Archive files
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@a8a3f3ad30e3422c9c7b888a15615d19a852ae32 # v3.1.3
         with:
           name: dist
           path: dist
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index fa908728..8f81945e 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -26,9 +26,9 @@ jobs:
           ["3.7", "3.8", "3.9", "3.10", "3.11", "3.12", "pypy3.8", "pypy3.9", "pypy3.10"]
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0
 
-      - uses: actions/setup-python@v4
+      - uses: actions/setup-python@65d7f2d534ac1bc67fcd62888c5f4f3d2cb2b236 # v4.7.1
         name: Install Python ${{ matrix.python_version }}
         with:
           python-version: ${{ matrix.python_version }}
diff --git a/docs/development/getting-started.rst b/docs/development/getting-started.rst
index cb751d67..a713eac8 100644
--- a/docs/development/getting-started.rst
+++ b/docs/development/getting-started.rst
@@ -73,5 +73,5 @@ The HTML documentation index can now be found at
 .. _`virtualenv`: https://pypi.org/project/virtualenv/
 .. _`pip`: https://pypi.org/project/pip/
 .. _`sphinx`: https://pypi.org/project/Sphinx/
-.. _`reStructured Text`: http://sphinx-doc.org/rest.html
+.. _`reStructured Text`: https://www.sphinx-doc.org/en/master/usage/restructuredtext/
 .. _`pre-commit`: https://pre-commit.com
diff --git a/docs/development/index.rst b/docs/development/index.rst
index c0aea8ac..767f0885 100644
--- a/docs/development/index.rst
+++ b/docs/development/index.rst
@@ -16,4 +16,4 @@ bug check out `what to put in your bug report`_.
     release-process
 
 .. _`GitHub`: https://github.com/pypa/packaging
-.. _`what to put in your bug report`: http://www.contribution-guide.org/#what-to-put-in-your-bug-report
+.. _`what to put in your bug report`: https://www.contribution-guide.org/#what-to-put-in-your-bug-report
diff --git a/docs/development/submitting-patches.rst b/docs/development/submitting-patches.rst
index fbdb5a4d..d05637a6 100644
--- a/docs/development/submitting-patches.rst
+++ b/docs/development/submitting-patches.rst
@@ -70,5 +70,5 @@ So, specifically:
 .. |black| replace:: ``black``
 .. _black: https://pypi.org/project/black/
 .. _`Write comments as complete sentences.`: https://nedbatchelder.com/blog/201401/comments_should_be_sentences.html
-.. _`syntax`: http://sphinx-doc.org/domains.html#info-field-lists
-.. _`Studies have shown`: http://www.ibm.com/developerworks/rational/library/11-proven-practices-for-peer-review/
+.. _`syntax`: https://www.sphinx-doc.org/en/master/usage/restructuredtext/field-lists.html
+.. _`Studies have shown`: https://www.microsoft.com/en-us/research/publication/characteristics-of-useful-code-reviews-an-empirical-study-at-microsoft/
diff --git a/src/packaging/_manylinux.py b/src/packaging/_manylinux.py
index 0a9cf414..ad62505f 100644
--- a/src/packaging/_manylinux.py
+++ b/src/packaging/_manylinux.py
@@ -90,7 +90,7 @@ def _glibc_version_string_confstr() -> Optional[str]:
     # https://github.com/python/cpython/blob/fcf1d003bf4f0100c/Lib/platform.py#L175-L183
     try:
         # Should be a string like "glibc 2.17".
-        version_string: str = getattr(os, "confstr")("CS_GNU_LIBC_VERSION")
+        version_string: Optional[str] = os.confstr("CS_GNU_LIBC_VERSION")
         assert version_string is not None
         _, version = version_string.rsplit()
     except (AssertionError, AttributeError, OSError, ValueError):
@@ -182,7 +182,7 @@ def _is_compatible(arch: str, version: _GLibCVersion) -> bool:
         return False
     # Check for presence of _manylinux module.
     try:
-        import _manylinux  # noqa
+        import _manylinux
     except ImportError:
         return True
     if hasattr(_manylinux, "manylinux_compatible"):
diff --git a/src/packaging/_parser.py b/src/packaging/_parser.py
index 4576981c..684df754 100644
--- a/src/packaging/_parser.py
+++ b/src/packaging/_parser.py
@@ -324,10 +324,7 @@ def _parse_marker_var(tokenizer: Tokenizer) -> MarkerVar:
 
 
 def process_env_var(env_var: str) -> Variable:
-    if (
-        env_var == "platform_python_implementation"
-        or env_var == "python_implementation"
-    ):
+    if env_var in ("platform_python_implementation", "python_implementation"):
         return Variable("platform_python_implementation")
     else:
         return Variable(env_var)
diff --git a/src/packaging/requirements.py b/src/packaging/requirements.py
index 0c00eba3..bdc43a7e 100644
--- a/src/packaging/requirements.py
+++ b/src/packaging/requirements.py
@@ -38,7 +38,7 @@ def __init__(self, requirement_string: str) -> None:
 
         self.name: str = parsed.name
         self.url: Optional[str] = parsed.url or None
-        self.extras: Set[str] = set(parsed.extras if parsed.extras else [])
+        self.extras: Set[str] = set(parsed.extras or [])
         self.specifier: SpecifierSet = SpecifierSet(parsed.specifier)
         self.marker: Optional[Marker] = None
         if parsed.marker is not None:
diff --git a/src/packaging/specifiers.py b/src/packaging/specifiers.py
index 94448327..2d015bab 100644
--- a/src/packaging/specifiers.py
+++ b/src/packaging/specifiers.py
@@ -11,17 +11,7 @@
 import abc
 import itertools
 import re
-from typing import (
-    Callable,
-    Iterable,
-    Iterator,
-    List,
-    Optional,
-    Set,
-    Tuple,
-    TypeVar,
-    Union,
-)
+from typing import Callable, Iterable, Iterator, List, Optional, Tuple, TypeVar, Union
 
 from .utils import canonicalize_version
 from .version import Version
@@ -697,7 +687,10 @@ def _pad_version(left: List[str], right: List[str]) -> Tuple[List[str], List[str
     left_split.insert(1, ["0"] * max(0, len(right_split[0]) - len(left_split[0])))
     right_split.insert(1, ["0"] * max(0, len(left_split[0]) - len(right_split[0])))
 
-    return (list(itertools.chain(*left_split)), list(itertools.chain(*right_split)))
+    return (
+        list(itertools.chain.from_iterable(left_split)),
+        list(itertools.chain.from_iterable(right_split)),
+    )
 
 
 class SpecifierSet(BaseSpecifier):
@@ -729,14 +722,8 @@ def __init__(
         # strip each item to remove leading/trailing whitespace.
         split_specifiers = [s.strip() for s in specifiers.split(",") if s.strip()]
 
-        # Parsed each individual specifier, attempting first to make it a
-        # Specifier.
-        parsed: Set[Specifier] = set()
-        for specifier in split_specifiers:
-            parsed.add(Specifier(specifier))
-
-        # Turn our parsed specifiers into a frozen set and save them for later.
-        self._specs = frozenset(parsed)
+        # Make each individual specifier a Specifier and save in a frozen set for later.
+        self._specs = frozenset(map(Specifier, split_specifiers))
 
         # Store our prereleases value so we can use it later to determine if
         # we accept prereleases or not.
diff --git a/tests/test_specifiers.py b/tests/test_specifiers.py
index ebcd9d98..a79b860e 100644
--- a/tests/test_specifiers.py
+++ b/tests/test_specifiers.py
@@ -235,8 +235,7 @@ def test_specifiers_hash(self, specifier):
 
     @pytest.mark.parametrize(
         ("left", "right", "op"),
-        itertools.chain(
-            *
+        itertools.chain.from_iterable(
             # Verify that the equal (==) operator works correctly
             [[(x, x, operator.eq) for x in SPECIFIERS]]
             +
@@ -260,8 +259,7 @@ def test_comparison_canonicalizes(self, left, right):
 
     @pytest.mark.parametrize(
         ("left", "right", "op"),
-        itertools.chain(
-            *
+        itertools.chain.from_iterable(
             # Verify that the equal (==) operator works correctly
             [[(x, x, operator.ne) for x in SPECIFIERS]]
             +
@@ -815,8 +813,7 @@ def test_specifiers_combine_not_implemented(self):
 
     @pytest.mark.parametrize(
         ("left", "right", "op"),
-        itertools.chain(
-            *
+        itertools.chain.from_iterable(
             # Verify that the equal (==) operator works correctly
             [[(x, x, operator.eq) for x in SPECIFIERS]]
             +
@@ -836,8 +833,7 @@ def test_comparison_true(self, left, right, op):
 
     @pytest.mark.parametrize(
         ("left", "right", "op"),
-        itertools.chain(
-            *
+        itertools.chain.from_iterable(
             # Verify that the equal (==) operator works correctly
             [[(x, x, operator.ne) for x in SPECIFIERS]]
             +
diff --git a/tests/test_structures.py b/tests/test_structures.py
index f8115e57..cc651cf6 100644
--- a/tests/test_structures.py
+++ b/tests/test_structures.py
@@ -8,11 +8,11 @@
 
 
 def test_infinity_repr():
-    repr(Infinity) == "Infinity"
+    assert repr(Infinity) == "Infinity"
 
 
 def test_negative_infinity_repr():
-    repr(NegativeInfinity) == "-Infinity"
+    assert repr(NegativeInfinity) == "-Infinity"
 
 
 def test_infinity_hash():
diff --git a/tests/test_version.py b/tests/test_version.py
index 8004c0cc..6cdbe190 100644
--- a/tests/test_version.py
+++ b/tests/test_version.py
@@ -667,8 +667,7 @@ def test_version_is_postrelease(self, version, expected):
         ("left", "right", "op"),
         # Below we'll generate every possible combination of VERSIONS that
         # should be True for the given operator
-        itertools.chain(
-            *
+        itertools.chain.from_iterable(
             # Verify that the less than (<) operator works correctly
             [
                 [(x, y, operator.lt) for y in VERSIONS[i + 1 :]]
@@ -710,8 +709,7 @@ def test_comparison_true(self, left, right, op):
         ("left", "right", "op"),
         # Below we'll generate every possible combination of VERSIONS that
         # should be False for the given operator
-        itertools.chain(
-            *
+        itertools.chain.from_iterable(
             # Verify that the less than (<) operator works correctly
             [
                 [(x, y, operator.lt) for y in VERSIONS[: i + 1]]