code: ## main function of AWS Lambda function
  import llama_index
  from llama_index import download_loader
  import boto3
  import json
  import urllib.parse
  from llama_index import SimpleDirectoryReader
  
  
  def main(event, context):
      # extracting s3 bucket and key information from SQS message
      print(event)
      s3_info = json.loads(event['Records'][0]['body'])
      bucket_name = s3_info['Records'][0]['s3']['bucket']['name']
      object_key = urllib.parse.unquote_plus(s3_info['Records'][0]['s3']['object']['key'], encoding='utf-8')
  
      
      try:
          # the first approach to rea =d the content of uploaded file. 
          S3Reader = download_loader("S3Reader", custom_path='/tmp/llamahub_modules')
          loader = S3Reader(bucket=bucket_name, key=object_key)
          documents = loader.load_data()
  
          # the second approach to read the content of uploaded file
          # Creating an S3 client
          # s3_client = boto3.client('s3')
          # response = s3_client.get_object(Bucket=bucket_name, Key=object_key)
          # file_content  = response['Body'].read().decode('utf-8')
          # save the file content to /tmp folder
          # tmp_file_path = f"/tmp/{object_key.split('/')[-1]}"
          # with open(tmp_file_path, "w") as f:
          #     tmp_file_path.write(file_content)
          # reader = SimpleDirectoryReader(input_files=tmp_file_path)
          # doc = reader.load_data()
          # print(f"Loaded {len(doc)} doc")
  
          ## TODO
          # ReIndex or Create New Index from document
          # Update or Insert into VectoDatabase
          # (Optional) Update or Insert into DocStorage DB
          # Update or Insert index to MongoDB
          # Can have Ingestion Pipeline with Redis Cache
          
          return {
              'statusCode': 200
          }
          
      #     # creating an index 
      except Exception as e:
          print(f"Error reading the file {object_key}: {str(e)}")
          return {
              'statusCode': 500,
              'body': json.dumps('Error reading the file')
          }
apis: llama_index.download_loader
extract_api: [((313, 352), 'json.loads', 'json.loads', (["event['Records'][0]['body']"], {}), "(event['Records'][0]['body'])\n", (323, 352), False, 'import json\n'), ((628, 692), 'llama_index.download_loader', 'download_loader', (['"""S3Reader"""'], {'custom_path': '"""/tmp/llamahub_modules"""'}), "('S3Reader', custom_path='/tmp/llamahub_modules')\n", (643, 692), False, 'from llama_index import download_loader\n'), ((1963, 1999), 'json.dumps', 'json.dumps', (['"""Error reading the file"""'], {}), "('Error reading the file')\n", (1973, 1999), False, 'import json\n')]