minor style fix
diff --git a/tests/test_numpy_array.cpp b/tests/test_numpy_array.cpp
index d422325..f8be722 100644
--- a/tests/test_numpy_array.cpp
+++ b/tests/test_numpy_array.cpp
@@ -125,5 +125,5 @@
         }
     );
 
-    sm.def("function_taking_uint64", [](uint64_t){ });
+    sm.def("function_taking_uint64", [](uint64_t) { });
 });