diff --git a/dj_database_url/__init__.py b/dj_database_url/__init__.py
index f580f90..7fbd116 100644
--- a/dj_database_url/__init__.py
+++ b/dj_database_url/__init__.py
@@ -31,6 +31,7 @@
 # Register database schemes in URLs.
 for key in SCHEMES.keys():
     urlparse.uses_netloc.append(key)
+del key
 
 
 # From https://docs.djangoproject.com/en/4.0/ref/settings/#databases