diff --git a/pythonosc/dispatcher.py b/pythonosc/dispatcher.py
index 680f26d..0ea9480 100644
--- a/pythonosc/dispatcher.py
+++ b/pythonosc/dispatcher.py
@@ -1,5 +1,4 @@
-"""Maps OSC addresses to handler functions
-"""
+"""Maps OSC addresses to handler functions"""
 
 import collections
 import inspect
diff --git a/pythonosc/osc_bundle_builder.py b/pythonosc/osc_bundle_builder.py
index ee28d6f..7b9bf20 100644
--- a/pythonosc/osc_bundle_builder.py
+++ b/pythonosc/osc_bundle_builder.py
@@ -25,9 +25,11 @@ def __init__(self, timestamp: int) -> None:
                        seconds since the epoch in UTC or IMMEDIATELY.
         """
         self._timestamp = timestamp
-        self._contents: List[osc_bundle.OscBundle] = []
+        self._contents: List[osc_bundle.OscBundle | osc_message.OscMessage] = []
 
-    def add_content(self, content: osc_bundle.OscBundle) -> None:
+    def add_content(
+        self, content: osc_bundle.OscBundle | osc_message.OscMessage
+    ) -> None:
         """Add a new content to this bundle.
 
         Args:
diff --git a/pythonosc/osc_message_builder.py b/pythonosc/osc_message_builder.py
index ebbc2cb..c17da45 100644
--- a/pythonosc/osc_message_builder.py
+++ b/pythonosc/osc_message_builder.py
@@ -96,7 +96,7 @@ def add_arg(self, arg_value: ArgValue, arg_type: Optional[str] = None) -> None:
             arg_type = self._get_arg_type(arg_value)
         if isinstance(arg_type, list):
             self._args.append((self.ARG_TYPE_ARRAY_START, None))
-            for v, t in zip(arg_value, arg_type):  # type: ignore[var-annotated, arg-type]
+            for v, t in zip(arg_value, arg_type):  # type: ignore[arg-type]
                 self.add_arg(v, t)
             self._args.append((self.ARG_TYPE_ARRAY_STOP, None))
         else:
diff --git a/pythonosc/osc_server.py b/pythonosc/osc_server.py
index b2fd5a9..aad0162 100644
--- a/pythonosc/osc_server.py
+++ b/pythonosc/osc_server.py
@@ -1,5 +1,4 @@
-"""OSC Servers that receive UDP packets and invoke handlers accordingly.
-"""
+"""OSC Servers that receive UDP packets and invoke handlers accordingly."""
 
 import asyncio
 import os
diff --git a/pythonosc/test/parsing/test_osc_types.py b/pythonosc/test/parsing/test_osc_types.py
index 052a161..55e70b3 100644
--- a/pythonosc/test/parsing/test_osc_types.py
+++ b/pythonosc/test/parsing/test_osc_types.py
@@ -85,10 +85,10 @@ def test_get_rgba(self):
             b"\x00\x00\x00\x01": (1, 4),
             b"\x00\x00\x00\x02": (2, 4),
             b"\x00\x00\x00\x03": (3, 4),
-            b"\xFF\x00\x00\x00": (4278190080, 4),
-            b"\x00\xFF\x00\x00": (16711680, 4),
-            b"\x00\x00\xFF\x00": (65280, 4),
-            b"\x00\x00\x00\xFF": (255, 4),
+            b"\xff\x00\x00\x00": (4278190080, 4),
+            b"\x00\xff\x00\x00": (16711680, 4),
+            b"\x00\x00\xff\x00": (65280, 4),
+            b"\x00\x00\x00\xff": (255, 4),
             b"\x00\x00\x00\x01GARBAGE": (1, 4),
         }
 
@@ -164,7 +164,7 @@ def test_get_timetag(self):
                 (datetime(1900, 1, 1, 0, 0, 0), 0),
                 8,
             ),
-            b"\x83\xaa\x7E\x80\x0A\x00\xB0\x0C": (
+            b"\x83\xaa\x7e\x80\x0a\x00\xb0\x0c": (
                 (datetime(1970, 1, 1, 0, 0, 0), 167817228),
                 8,
             ),