Lambda function should be triggered when any changes in S3 object with respect to file and apply those findings in anther s3 bucket

import json import urllib.parse import boto3

print('Loading function') s3 = boto3.client('s3') def lambda_handler(event, context): #print("Received event: " + json.dumps(event, indent=2))

# Get the object from the event and show its content type
bucket = event["Records"][0]["s3"]["bucket"]['s3bucket001forlambda01']
key = urllib.parse.unquote_plus(event["Records"][0]["s3"]["object"]["Notes"], encoding='utf-8')
try:
    response = s3.get_object(Bucket=bucket, Key=key)
    print("CONTENT TYPE: " + response['ContentType'])
    return response['ContentType']
except Exception as e:
    print(e)
    print('Error getting object {} from bucket {}. Make sure they exist and your bucket is in the same region as this function.'.format(key, bucket))
    raise e

Here is my code -- still getting key error

Response { "errorMessage": "'s3bucket001forlambda01'", "errorType": "KeyError", "stackTrace": [ " File "/var/task/lambda_function.py", line 14, in lambda_handler\n bucket = event["Records"][0]["s3"]["bucket"]['s3bucket001forlambda01']\n" ] }

Function Logs START RequestId: eb0f25c5-e96f-4db0-83b3-702a23203847 Version: $LATEST [ERROR] KeyError: 's3bucket001forlambda01' Traceback (most recent call last):   File "/var/task/lambda_function.py", line 14, in lambda_handler     bucket = event["Records"][0]["s3"]["bucket"]['s3bucket001forlambda01'] END RequestId: eb0f25c5-e96f-4db0-83b3-702a23203847

You should not include ['s3bucket001forlambda01'] in there. Instead you should use ["name"], just as I wrote in my example. You get the bucket name and object key from the event object. You should not provide them youself.