diff --git a/glean-core/python/glean/_loader.py b/glean-core/python/glean/_loader.py
index 2d918a7f7c..1b9d4efcb5 100644
--- a/glean-core/python/glean/_loader.py
+++ b/glean-core/python/glean/_loader.py
@@ -41,7 +41,7 @@
     "timing_distribution": metrics.TimingDistributionMetricType,
     "uuid": metrics.UuidMetricType,
     "jwe": metrics.JweMetricType,
-    "quantity": metrics.QuantityMetricType
+    "quantity": metrics.QuantityMetricType,
 }