s3bucket with python

hi team i was trying to do read file from s3bucket. as oof now am able to download the file reading that same file
instead of downloading the file can i read from s3 bucket
some one please suggest me the code,how to read file from s3bucket


import os, sys, csv,json
from itertools import product
import requestsfrom requests_aws4auth
import AWS4Authimport boto3import botocore
import configfrom elasticsearch
import helpers,Elasticsearches = Elasticsearch("localhost:9200")

s3 = boto3.resource('s3')
ACCESS=config.s3bucket['aws_access_key']
SECRET=config.s3bucket['aws_secret_key']
url_e=config.s3bucket['url']

client = boto3.client(service_name="s3", region_name="us-east-1",endpoint_url=url_e,verify=False,aws_access_key_id = ACCESS,aws_secret_access_key= SECRET)

client.download_file('s3_bucket','sourcefile.csv','sourcefile.csv')
print ("Downloading object %s from bucket %s" % ('sourcefile.csv','s3_bucket'))

#step1: file split into two files

if os.path.exists('file1.csv'):
    print('File is previously present and have been deleted !')
    os.remove('file1.csv')
if os.path.exists('file2.csv'):
    print('File is previously present and have been deleted !')
    os.remove('file2.csv')

condition = 0
header = []

with open('sourcefile.csv', 'r', encoding='UTF-8') as file:
    for lines in file:
        if condition ==0:
            header = lines.strip('\n').split(',')
        elif condition < 2:
            with open('file1.csv', 'a', encoding='UTF-8') as file_01:
                if os.stat('file1.csv').st_size == 0:
                    file_01.write(','.join(header) + '\n')
                    file_01.write(lines.strip('\n') + '\n')
        elif condition >= 3:
            with open('file2.csv', 'a', encoding='UTF-8') as file_02:
                file_02.write(lines.strip('\n') + '\n')
condition += 1
print('file spliting completed')

#step2:merging both files and updating header.

with open(r'file1.csv','rt')as f:
    data1 = csv.reader(f,delimiter=",")
    list1= [row for row in data1]
with open(r'file2.csv','rt')as f:
    data2 = csv.reader(f,delimiter=",")
    list2= [row for row in data2]
header= ["dept_id","dept_role","dept_name","dept_date","dept_service","id","name","start_time","end_time","user","manufacturing","exp"]
if os.path.exists('BAY23_merge.csv'):
    print('File is previously present and have been deleted !')
    os.remove('BAY23_merge.csv')
with open('file_merge.csv', 'w', newline='') as csvfile:
    csvwriter = csv.writer(csvfile)
    csvfile.write(','.join(header)+'\n')
    for r in list2[1:]:
        csvwriter.writerow(list1[1]+r)
print('files has merged and header has updated')

#step3:loading data into elasticsearch:

from elasticsearch import helpers,Elasticsearches = Elasticsearch("localhost:9200")
with open('file_merge.csv') as f:
    reader = csv.DictReader(f)
    helpers.bulk(es, reader, index='test_data_sample', doc_type='test-sample')

print('data loaded into ES')