Text file S3 triggered lambda processes the file and creates the result in a new text file in same S3 location

S3ComprehendMedicalLambda.py

import json
import urllib.parse
import boto3
import os

print('Loading function')

s3 = boto3.client('s3')
comprehend = boto3.client('comprehendmedical')

def executeComprehendService(text):
    comprehendText = ''
    entities =  comprehend.detect_entities(Text=text)
    
    for entity in entities["Entities"]:
        comprehendText += "- {}".format(entity["Text"]) + '\n'
        comprehendText += "   Type: {}".format(entity["Type"]) + '\n'
        comprehendText += "   Category: {}".format(entity["Category"]) + '\n'
        if(entity["Traits"]):
            comprehendText += "   Traits:" + '\n'
            for trait in entity["Traits"]:
                comprehendText += "    - {}".format(trait["Name"]) + '\n'
    comprehendText +=  '\n'
    
    return comprehendText

def writeComprehendMedicalTextToS3File(comprehendText, bucketName, textFileName):
    print('Loading writeComprehendMedicalTextToS3File')
    generateFilePath = 'Comprehend_' + os.path.splitext(textFileName)[0] + '.txt'
    s3.put_object(Body=comprehendText, Bucket=bucketName, Key=generateFilePath)
    print('Generated ' + generateFilePath)

def lambda_handler(event, context):
    # Get the object from the event and show its content type
    bucket = event['Records'][0]['s3']['bucket']['name']
    key = urllib.parse.unquote_plus(event['Records'][0]['s3']['object']['key'], encoding='utf-8')
    try:
        if('Comprehend_' not in key):
            textFile = s3.get_object(Bucket=bucket, Key=key)
            content = textFile['Body'].read().decode('utf-8') 
            comprehendText = executeComprehendService(json.dumps(content))
            writeComprehendMedicalTextToS3File(comprehendText, bucket, key)
        
        print('Processing Done!')
    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