Setting aws temp credentials in python - AttributeError

Question

I am trying to create a python script which will set aws temp credentials for me , rather than me having to manually run these following commands each time :

export AWS_PROFILE=terraformlive

aws sts get-session-token --serial-number "arn:aws:iam::595659205553:mfa/my-device" --token-code 123456

export AWS_ACCESS_KEY_ID=

export AWS_SECRET_ACCESS_KEY=

export AWS_DEFAULT_REGION=

export AWS_SESSION_TOKEN=

I have made a start on my python script but am not sure why I keep seeing this error , I have looked around on other solutions on stackoverflow but i really can't seem to figure out why my script is complaining and showing me the following error :

AttributeError: 'list' object has no attribute 'writelines'

import os
import boto3 as b

mfa_serial_number = "arn:aws:iam::595659205553:mfa/my-device"
mfa_otp = input("Enter your otp:" )

def get_sts(mfa_serial_number, mfa_otp):
    
    session = b.Session(profile_name='terraformlive', region_name='eu-west-1')
    sts = session.client('sts')
    if mfa_serial_number is not None:
        response = sts.get_session_token(
            SerialNumber=mfa_serial_number, TokenCode=mfa_otp)
    else:
        response = sts.get_session_token()
    temp_credentials = response['Credentials']
    print(temp_credentials)
    token_reponse = ["[temp-token] \n", "aws_access_key_id = " + temp_credentials["AccessKeyId"], "\n", "aws_secret_access_key = " + temp_credentials["SecretAccessKey"],"\n", "aws_session_token = " + temp_credentials["SessionToken"],"\n"]
    # Look for the temp-token profile
    pfile = "[temp-token]"
    with open("/Users/mrdavado/.aws/credentials", "r") as credentials:
     aws_credential_file = credentials.readlines()
     #print(aws_credential_file)
    for line in aws_credential_file:
         if line.find(pfile) != -1:
             print('Profile Exists!')
             #Prints the line number where the word was found
             profile_line = aws_credential_file.index(line)
             new_aws_access_key_line_num = profile_line + 1
             new_secret_access_key_line_num = profile_line + 2
             new_session_token_key_line_num = profile_line + 3
             print("its still working", profile_line)
             print(new_aws_access_key_line_num)
         else:
          aws_credential_file.writelines([token_reponse])
          credentials.close()
    

get_sts(mfa_serial_number, mfa_otp)

I have looked around on stackoverflow but cannot seem to find anything. I want my python script to be able to run aws sts get-session-token and set the temp credentials for me.

Answer 1

aws_credential_file.writelines([token_reponse]) I think this should be credentials not aws_credential_file?