add remove_domain_suffix filter

ansible.cfg

@@ -3,6 +3,7 @@ ask_vault_pass = True
 roles_path = ./roles
 retry_files_enabled = False
 inventory = ./hosts
+filter_plugins = ./filter_plugins
 ansible_managed = Ansible managed, modified on %Y-%m-%d %H:%M:%S
 nocows = 1
 forks = 15

filter_plugins/net_utils.py

@@ -0,0 +1,13 @@
+import dns.name
+
+
+class FilterModule:
+    def filters(self):
+        return {
+            "remove_domain_suffix": remove_domain_suffix,
+        }
+
+
+def remove_domain_suffix(name):
+    parent = dns.name.from_text(name).parent()
+    return parent.to_text()