Get a session token with Amazon STS using an Amazon SDK

Get a session token by passing an MFA token and use it to list Amazon S3 buckets for the account.

def list_buckets_with_session_token_with_mfa(mfa_serial_number, mfa_totp, sts_client):
    """
    Gets a session token with MFA credentials and uses the temporary session
    credentials to list Amazon S3 buckets.

    Requires an MFA device serial number and token.

    :param mfa_serial_number: The serial number of the MFA device. For a virtual MFA
                              device, this is an Amazon Resource Name (ARN).
    :param mfa_totp: A time-based, one-time password issued by the MFA device.
    :param sts_client: A Boto3 STS instance that has permission to assume the role.
    """
    if mfa_serial_number is not None:
        response = sts_client.get_session_token(
            SerialNumber=mfa_serial_number, TokenCode=mfa_totp)
    else:
        response = sts_client.get_session_token()
    temp_credentials = response['Credentials']

    s3_resource = boto3.resource(
        's3',
        aws_access_key_id=temp_credentials['AccessKeyId'],
        aws_secret_access_key=temp_credentials['SecretAccessKey'],
        aws_session_token=temp_credentials['SessionToken'])

    print(f"Buckets for the account:")
    for bucket in s3_resource.buckets.all():
        print(bucket.name)