diff --git a/tools/bzl/license-map.py b/tools/bzl/license-map.py
index 74a84cc..4856726 100644
--- a/tools/bzl/license-map.py
+++ b/tools/bzl/license-map.py
@@ -35,7 +35,7 @@
       continue
 
     handled_rules.append(rule_name)
-    for c in child.getchildren():
+    for c in list(child):
       if c.tag != "rule-input":
         continue