diff --git a/stdlib/internal/internal.codon b/stdlib/internal/internal.codon
index 092ff896..f627d23d 100644
--- a/stdlib/internal/internal.codon
+++ b/stdlib/internal/internal.codon
@@ -2,7 +2,8 @@
 
 from internal.gc import (
     free, register_finalizer, seq_alloc,
-    seq_alloc_atomic, seq_gc_add_roots, alloc_uncollectable
+    seq_alloc_atomic, seq_gc_add_roots, alloc_uncollectable,
+    alloc_atomic_uncollectable, atomic
 )
 
 @pure
diff --git a/stdlib/internal/python.codon b/stdlib/internal/python.codon
index 8660e130..c207e343 100644
--- a/stdlib/internal/python.codon
+++ b/stdlib/internal/python.codon
@@ -1897,8 +1897,12 @@ class _PyWrap:
         return cobj()
 
     def wrap_to_py(o) -> cobj:
-        pytype = _PyWrap.py_type(type(o))
-        obj = Ptr[PyWrapper[type(o)]](alloc_uncollectable(sizeof(type(o))))
+        O = type(o)
+        P = PyWrapper[O]
+        sz = sizeof(P)
+        pytype = _PyWrap.py_type(O)
+        mem = alloc_atomic_uncollectable(sz) if atomic(O) else alloc_uncollectable(sz)
+        obj = Ptr[P](mem.as_byte())
         obj[0] = PyWrapper(PyObject(1, pytype), o)
         return obj.as_byte()