Sample code for AWS IAM User assume IAM Role

import boto3

ACCESS_KEY_ID="xxxxxxxxxxxxx"
aws_secret_access_key = "xxxxxxxxxxxxx"

role_arn = 'arn:aws:iam::911111111111:role/xxxx-role'

session = boto3.Session(aws_access_key_id=ACCESS_KEY_ID,
                            aws_secret_access_key=SECRET_ACCESS_KEY,
                            region_name="us-east-1")

sts_client = session.client("sts")
#获取 IAM 用户的 temporary credentials
credentials = sts_client.assume_role(RoleArn=role_arn, RoleSessionName="a-session")

#使用 temporary credentials 创建一个 S3 client
s3_client = boto3.client("s3",
                         aws_access_key_id=credentials['Credentials']["AccessKeyId"],
                         aws_secret_access_key=credentials['Credentials']            ["SecretAccessKey"],
                        aws_session_token=credentials['Credentials']["SessionToken"])
s3_client.upload_file("filefullpath", "bucket-name-not-arn", "object_key")

A piece of sample code, how to use Python boto3 to first log in to sts using the AK SK of an IAM User.

Then inherit an IAM Role.

Finally, perform a specific operation, such as uploading files to S3 bucket in the code.