diff --git a/plugins/modules/ec2_placement_group_info.py b/plugins/modules/ec2_placement_group_info.py
index 96451d69ce5..7ec7f62fd92 100644
--- a/plugins/modules/ec2_placement_group_info.py
+++ b/plugins/modules/ec2_placement_group_info.py
@@ -6,7 +6,7 @@
 __metaclass__ = type
 
 
-DOCUMENTATION = '''
+DOCUMENTATION = r'''
 ---
 module: ec2_placement_group_info
 version_added: 1.0.0
@@ -51,7 +51,7 @@
 '''
 
 
-RETURN = '''
+RETURN = r'''
 placement_groups:
   description: Placement group attributes
   returned: always
@@ -107,7 +107,7 @@ def get_placement_groups_details(connection, module):
 
 def main():
     argument_spec = dict(
-        names=dict(type='list', default=[])
+        names=dict(type='list', default=[], elements='str')
     )
 
     module = AnsibleAWSModule(