diff --git a/setup.py b/setup.py
index 204ee2cc0..53b221e33 100644
--- a/setup.py
+++ b/setup.py
@@ -2,6 +2,6 @@
 
 setup(
     name="guided-diffusion",
-    py_modules=["guided_diffusion"],
+    packages=["guided_diffusion"],
     install_requires=["blobfile>=1.0.5", "torch", "tqdm"],
 )