internal change

PiperOrigin-RevId: 241954724
diff --git a/package.bzl b/package.bzl
index ae42990..6ec6afe 100644
--- a/package.bzl
+++ b/package.bzl
@@ -73,5 +73,5 @@
     )
 
 def _maybe(repo_rule, name, **kwargs):
-    if name not in native.existing_rules():
+    if not native.existing_rule(name):
         repo_rule(name = name, **kwargs)