Uploading Lambda response to S3 bucket and reading it again issue

Hi,

I have a lambda function that makes a call to the external Azure API and return a JSON object. I am able to upload the same JSON object to S3 successfully but while reading the same file, getting an error about "errorType": "JSONDecodeError",

# Main Azure API Block
def get_subscription_assignment_roles(subscriptions,access_token):
    try:
        # print(f"get_subscription_assignment_roles for total {len(subscriptions)} subscriptions" )
        assignment_roles = []
        for subscription in subscriptions[:5]:
            subscription_id = subscription['name']
            url = f"https://management.azure.com/subscriptions/{subscription_id}/providers/Microsoft.Authorization/roleAssignments?api-version=2022-04-01"
            # breare_toke = f"Bearer ${access_token}"
            # print(breare_toke)
            response = requests.get(url,headers={'Authorization': f'Bearer {access_token}'})
            response.raise_for_status()
            jsonResponse = response.json()
            # print(f"get_subscription_assignment_roles.status_code: ${response.status_code}")
            # print(f"get_subscription_assignment_roles.len: ",len(jsonResponse["value"]))
            if(len(jsonResponse["value"]) > 0):
                for assignment_role in jsonResponse["value"]:
                    if(assignment_role['properties']['principalType'] == "Group"):
                        assignment_roles.append(json.dumps({
                            'id':assignment_role['id'],
                            'principal_id':assignment_role['properties']['principalId'],
                            'account_id':subscription_id,
                            'role_definition_id':assignment_role['properties']['roleDefinitionId'],
                            'account_name':subscription['properties']['displayName'],
                            'created_on':assignment_role['properties']['createdOn'],
                            'updated_on':assignment_role['properties']['updatedOn']
                        }).encode('utf-8'))
        
        return assignment_roles
    except Exception as err:
        print(f"get_subscription_assignment_roles.error: {err}")
        raise err


# Function to upload file to S3 Bucket
def store_payload_into_bucket(assignment_roles):
    # print("inside put_dynamodb_item")
    try:
        # print(f'store_payload_into_bucket: {assignment_roles}')
        bucket_name = os.environ['permission_data_bucket']
        today = date.today()
        file_name = f"azure/datapayload_{today}.json" # platform/assignment_role_data_{datetime}
        table_name = os.environ['dynamodb_id']
        client = boto3.client('s3')
        assignment_roles = str(assignment_roles)
        try:
            client.put_object(Bucket=bucket_name,Key=file_name,Body=assignment_roles)
            return {
                'statusCode':200,
                'body': {'key':file_name,'bucket_id':bucket_name}
            }
        except Exception as err:
            return {
                'statusCode':500,
                'body':f'Error: {str(err)}'
            }
    except Exception as err:
        raise err


# Function to read the same file again:
def read_payload_from_bucket(event):
    # print("inside put_dynamodb_item")
    try:
        print(f'read_payload_from_bucket: {event}')
        bucket_name = os.environ['permission_data_bucket']
        today = date.today()
        file_name = f"azure/datapayload_{today}.json" # platform/assignment_role_data_{datetime}
        table_name = os.environ['dynamodb_id']
        client = boto3.client('s3')
        response = client.get_object(Bucket=event['bucket_id'],Key=event['key'])
        json_data = response['Body'].read()
        parsed_data = json.loads(json_data)
        print(f'Response data: {parsed_data}')

    except Exception as err:
        raise err

Here is the error. event tried decoding data before doing json.loads() but still no luck. can anyone help here.

{
  "errorMessage": "Expecting value: line 1 column 2 (char 1)",
  "errorType": "JSONDecodeError",
  "stackTrace": [
    "  File \"/var/task/azure_get_assignment_role_data.py\", line 49, in lambda_handler\n    read_payload_from_bucket(response['body'])\n",
    "  File \"/var/task/azure_get_assignment_role_data.py\", line 221, in read_payload_from_bucket\n    raise err\n",
    "  File \"/var/task/azure_get_assignment_role_data.py\", line 217, in read_payload_from_bucket\n    parsed_data = json.loads(json_data)\n",
    "  File \"/var/lang/lib/python3.8/json/__init__.py\", line 357, in loads\n    return _default_decoder.decode(s)\n",
    "  File \"/var/lang/lib/python3.8/json/decoder.py\", line 337, in decode\n    obj, end = self.raw_decode(s, idx=_w(s, 0).end())\n",
    "  File \"/var/lang/lib/python3.8/json/decoder.py\", line 355, in raw_decode\n    raise JSONDecodeError(\"Expecting value\", s, err.value) from None\n"
  ]
}