s3 replication cross region within same AWS account

file.py

import boto3, os, botocore, traceback
from botocore.exceptions import ClientError

s3 = boto3.client('s3')

# READ VALUES FROM ENVIRONMENT VARIABLES
source_s3_bucket = os.environ['source_s3_bucket']

#kms_keyid = os.environ['Kms_Keyid']

# APPEND REGION NAME FOR DESTINATION BUCKET
dest_s3_bucket = source_s3_bucket + '-rep-us-east-2'

# CREATE S3 BUCKET LIST
buckets = [source_s3_bucket, dest_s3_bucket]

# VERIFY IF BUCKET EXISTS
def check_bucket(bucket_name):
    try:
        s3.head_bucket(Bucket=bucket_name)
        print("Bucket Exists!")
        return True
    except botocore.exceptions.ClientError as e:
        error_code = int(e.response['Error']['Code'])   # IF A CLIENT ERROR IS THROWN, THEN CHECK THAT IT WAS A 404 ERROR.
        if error_code == 403:                           # YOU DONT HAVE ACCESS TO BUCKET
            print("Private Bucket. Forbidden Access!")
            return True
        elif error_code == 404:                         # IF IT WAS A 404 ERROR, THEN THE BUCKET DOES NOT EXIST
            print("Bucket Does Not Exist! Creating Bucket.....")
            create_bucket(bucket_name)
            print("Bucket Created")
            return False


# CREATE S3 BUCKET
def create_bucket(bucket_name):
    s3.create_bucket(
    ACL='private',
    Bucket=bucket_name,
    CreateBucketConfiguration={
        'LocationConstraint': 'us-east-2'
    }
)


# GET BUCKET VERSIONING
def check_versioning(bucket_name):
    bucket_response = s3.get_bucket_versioning(Bucket=bucket_name)
    try:
        status = bucket_response['Status']
    except KeyError:
        print('Versioning not ENABLED. Enabling versioning for ' + bucket_name)
        enable_versioning(bucket_name)
    else:
        if status == 'Enabled':
            print('Versioning already ENABLED - ' + bucket_name)




# ENABLE VERSIONING
def enable_versioning(bucket_name):
    s3.put_bucket_versioning(
    Bucket=bucket_name,
    VersioningConfiguration={
        'Status': 'Enabled'
    }
)

# ENABLE REPLICATION ON SOURCE BUCKET
def enable_replication(source_s3_bucket):
    s3.put_bucket_replication(
    Bucket=source_s3_bucket,
    ReplicationConfiguration={
        "Role": "arn:aws:iam::142705040095:role/service-role/s3crr_role_for_vm-managed-bucket-rep-checking_to_vm-managed-buck",
        "Rules": [
            {
                "ID": "vm-managed-s3-bucket-replication",
                "Priority": 1,
                "Filter": {},
                "Status": "Enabled",
                "Destination": {
                    "Bucket": "arn:aws:s3:::vm-managed-bucket-for-rep-rep-us-east-2"
                },
                "DeleteMarkerReplication": {
                    "Status": "Disabled"
                }
            }
        ]
    }
)


for bucket in buckets:
    check_bucket(bucket)
    check_versioning(bucket)
    try:
        rep_status = s3.get_bucket_replication(Bucket=source_s3_bucket)
        data = str(rep_status['ReplicationConfiguration']['Rules'][0]['Status'])
        print(data)
    except ClientError as e:
        error_code = str(e.response['Error']['Code'])
        print(error_code)
        if error_code == 'ReplicationConfigurationNotFoundError':
            print('Enabling Replication on Bucket ' + source_s3_bucket)
            enable_replication(source_s3_bucket)

Error Received while handling check_replication method:

Bucket Exists!
Versioning already ENABLED - vm-managed-bucket-for-rep
Traceback (most recent call last):
File "create_and_update_s3_bucket.py", line 106, in
check_replication(bucket)
File "create_and_update_s3_bucket.py", line 63, in check_replication
Bucket=bucket_name
File "/usr/local/lib/python3.6/dist-packages/botocore/client.py", line 276, in _api_call
return self._make_api_call(operation_name, kwargs)
File "/usr/local/lib/python3.6/dist-packages/botocore/client.py", line 586, in _make_api_call
raise error_class(parsed_response, operation_name)
botocore.exceptions.ClientError: An error occurred (ReplicationConfigurationNotFoundError) when calling the GetBucketReplication operation: The replication configuration was not found

except ClientError as e:
try this instead of botocore.exceptions.ClientError

except ClientError as e:
try this instead of botocore.exceptions.ClientError

I have added the new updated Gist. Check the newest revision.

Actually the method that I was calling get_bucket_replication() was itself generating the exception, which was earlier outside the try block. Not the evaluation condition inside the try. So kept the method get_bucket_replication() itself under try and could catch the exception error code.