diff --git a/changelogs/fragments/openstack_inventory-optional-region.yaml b/changelogs/fragments/openstack_inventory-optional-region.yaml
new file mode 100644
index 00000000000..210145e1969
--- /dev/null
+++ b/changelogs/fragments/openstack_inventory-optional-region.yaml
@@ -0,0 +1,8 @@
+---
+bugfixes:
+  - openstack_inventory.py dynamic inventory file
+    fixed the plugin to the script so that it will work with current
+    ansible-inventory.
+    Also redirect stdout before dumping the ouptput, because not doing
+    so will cause JSON parse errors in some cases.
+    (https://github.com/ansible/ansible/pull/43432)
diff --git a/contrib/inventory/openstack_inventory.py b/contrib/inventory/openstack_inventory.py
index 1bb5e17de95..81237a7bf22 100755
--- a/contrib/inventory/openstack_inventory.py
+++ b/contrib/inventory/openstack_inventory.py
@@ -57,6 +57,7 @@ import os
 import sys
 import time
 from distutils.version import StrictVersion
+from io import StringIO
 
 try:
     import json
@@ -81,7 +82,8 @@ def get_groups_from_server(server_vars, namegroup=True):
     groups.append(cloud)
 
     # Create a group on region
-    groups.append(region)
+    if region:
+        groups.append(region)
 
     # And one by cloud_region
     groups.append("%s_%s" % (cloud, region))
@@ -235,6 +237,8 @@ def parse_args():
 def main():
     args = parse_args()
     try:
+        # openstacksdk library may write to stdout, so redirect this
+        sys.stdout = StringIO()
         config_files = cloud_config.CONFIG_FILES + CONFIG_FILES
         sdk.enable_logging(debug=args.debug)
         inventory_args = dict(
@@ -255,6 +259,7 @@ def main():
 
         inventory = sdk_inventory.OpenStackInventory(**inventory_args)
 
+        sys.stdout = sys.__stdout__
         if args.list:
             output = get_host_groups(inventory, refresh=args.refresh, cloud=args.cloud)
         elif args.host: