diff --git a/tests/test_buffers.py b/tests/test_buffers.py
index 0e70b3a065..5d33625ba4 100644
--- a/tests/test_buffers.py
+++ b/tests/test_buffers.py
@@ -222,4 +222,7 @@ def test_ctypes_from_buffer():
 
 
 def test_buffer_docstring():
-    assert m.get_buffer_info.__doc__.strip() == "get_buffer_info(arg0: Buffer) -> pybind11_tests.buffers.buffer_info"
+    assert (
+        m.get_buffer_info.__doc__.strip()
+        == "get_buffer_info(arg0: Buffer) -> pybind11_tests.buffers.buffer_info"
+    )