Update ec2_instance find_instances to fix incompatibility with Python…

… 3.8 (#767)

Update ec2_instance find_instances to fix incompatibility with Python 3.8

SUMMARY

Update ec2_instance find_instances to use temporary dict. instead of inline changes. Fixes #709

ISSUE TYPE

Bugfix Pull Request

COMPONENT NAME

ec2_instance
ADDITIONAL INFORMATION
Current ec2_module iterates over a filters dictionary to perform hyphen to underscore substitution while popping keys in the process. This is not compatible with Python 3.8. I have simply created a second dictionary, I can also create a shallow copy via the copy() module if the team prefers.

Reviewed-by: Bikouo Aubin <None>
Reviewed-by: Alina Buzachis <None>
Reviewed-by: Mark Chappell <None>
(cherry picked from commit 0ca065c)

changelogs/fragments/709-ec_2_instance-python-3-8-compatibility.yml

@@ -0,0 +1,3 @@
+---
+bugfixes:
+  - ec2_instance - ec2_instance module broken in Python 3.8 - dict keys modified during iteration (https://github.com/ansible-collections/amazon.aws/issues/709).

plugins/modules/ec2_instance.py

@@ -1463,20 +1463,25 @@ def change_network_attachments(instance, params):
 
 def find_instances(ids=None, filters=None):
     paginator = client.get_paginator('describe_instances')
+    sanitized_filters = dict()
+
     if ids:
         params = dict(InstanceIds=ids)
     elif filters is None:
         module.fail_json(msg="No filters provided when they were required")
     else:
         for key in list(filters.keys()):
             if not key.startswith("tag:"):
-                filters[key.replace("_", "-")] = filters.pop(key)
-        params = dict(Filters=ansible_dict_to_boto3_filter_list(filters))
+                sanitized_filters[key.replace("_", "-")] = filters[key]
+            else:
+                sanitized_filters[key] = filters[key]
+        params = dict(Filters=ansible_dict_to_boto3_filter_list(sanitized_filters))
 
     try:
         results = _describe_instances(**params)
     except (botocore.exceptions.BotoCoreError, botocore.exceptions.ClientError) as e:
         module.fail_json_aws(e, msg="Could not describe instances")
+
     retval = list(results)
     return retval