diff --git a/push_action/cache.py b/push_action/cache.py
index b769c39..a7e4e80 100644
--- a/push_action/cache.py
+++ b/push_action/cache.py
@@ -7,7 +7,8 @@
 from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:  # pragma: no cover
-    from typing import Any, Iterator
+    from typing import Any
+    from collections.abc import Iterator
 
 
 class InMemoryCache:
diff --git a/push_action/run.py b/push_action/run.py
index d4c52b4..594862d 100644
--- a/push_action/run.py
+++ b/push_action/run.py
@@ -186,7 +186,7 @@ def unprotect_reviews() -> None:
 def protect_reviews() -> None:
     """Re-add pull request review protection for target branch"""
     # Retrieve data
-    with open("tmp_protection_rules.json", "r", encoding="utf8") as handle:
+    with open("tmp_protection_rules.json", encoding="utf8") as handle:
         data = json.load(handle)
 
     # Add protection
diff --git a/push_action/utils.py b/push_action/utils.py
index bc4e1e7..49e3427 100644
--- a/push_action/utils.py
+++ b/push_action/utils.py
@@ -21,7 +21,8 @@
 from push_action.validate import validate_rest_api_base_url
 
 if TYPE_CHECKING:  # pragma: no cover
-    from typing import Callable, List, Union
+    from typing import List, Union
+    from collections.abc import Callable
 
 
 LOGGER = logging.getLogger("push_action.utils")
diff --git a/push_action/validate.py b/push_action/validate.py
index 00acbc9..a2be3fc 100644
--- a/push_action/validate.py
+++ b/push_action/validate.py
@@ -40,7 +40,7 @@ def validate_conclusions(conclusions: list[str]) -> list[str]:
         )
 
     # Remove redundant entries and conform to lowercase
-    conclusions = list(set(conclusion.lower() for conclusion in conclusions))
+    conclusions = list({conclusion.lower() for conclusion in conclusions})
 
     for conclusion in conclusions:
         invalid_conclusions: list[str] = []
diff --git a/setup.py b/setup.py
index b5fe942..747404d 100644
--- a/setup.py
+++ b/setup.py
@@ -14,7 +14,7 @@
 
 TOP_DIR = Path(__file__).parent.resolve()
 
-with open(TOP_DIR / "push_action" / "__init__.py", "r", encoding="utf8") as handle:
+with open(TOP_DIR / "push_action" / "__init__.py", encoding="utf8") as handle:
     for line in handle.readlines():
         version = re.findall(r'__version__ = "(.*)"', line)
         if version: