diff --git a/python-dicts/README.md b/python-dicts/README.md
index ac4a108380..c957af0315 100644
--- a/python-dicts/README.md
+++ b/python-dicts/README.md
@@ -1,3 +1,5 @@
 # Dictionaries in Python
 
 This folder provides the code examples for the Real Python tutorial [Dictionaries in Python](https://realpython.com/python-dicts/).
+
+The code requires Python 3.9 or later and has no third-party dependencies.
diff --git a/python-dicts/dict_zip.py b/python-dicts/dict_zip.py
index 58ad9ff66d..23055ebc6c 100644
--- a/python-dicts/dict_zip.py
+++ b/python-dicts/dict_zip.py
@@ -1,4 +1,18 @@
-cities = ["Colorado", "Chicago", "Boston", "Minnesota", "Milwaukee", "Seattle"]
-teams = ["Rockies", "White Sox", "Red Sox", "Twins", "Brewers", "Mariners"]
+places = [
+    "Colorado",
+    "Chicago",
+    "Boston",
+    "Minnesota",
+    "Milwaukee",
+    "Seattle",
+]
+teams = [
+    "Rockies",
+    "White Sox",
+    "Red Sox",
+    "Twins",
+    "Brewers",
+    "Mariners",
+]
 
-print(dict(zip(cities, teams, strict=False)))
+print(dict(zip(places, teams)))
diff --git a/python-dicts/membership.py b/python-dicts/membership.py
index b3c1d6fc0e..1494f30621 100644
--- a/python-dicts/membership.py
+++ b/python-dicts/membership.py
@@ -11,16 +11,16 @@
 
 # Run timeit to compare the membership test
 time_in_dict = timeit.timeit(
-    '"Milwaukee" in MLB_teams', globals=globals(), number=1000000
+    '"Milwaukee" in MLB_teams', globals=globals(), number=1_000_000
 )
 time_in_keys = timeit.timeit(
-    '"Milwaukee" in MLB_teams.keys()', globals=globals(), number=1000000
+    '"Milwaukee" in MLB_teams.keys()', globals=globals(), number=1_000_000
 )
 time_not_in_dict = timeit.timeit(
-    '"Indianapolis" in MLB_teams', globals=globals(), number=1000000
+    '"Indianapolis" in MLB_teams', globals=globals(), number=1_000_000
 )
 time_not_in_keys = timeit.timeit(
-    '"Indianapolis" in MLB_teams.keys()', globals=globals(), number=1000000
+    '"Indianapolis" in MLB_teams.keys()', globals=globals(), number=1_000_000
 )
 
 print(