from datetime import datetime


def assert_isoformat_utc(time_str):
    """
    Asserts if a date formats as "YYYY-MM-DDThh:mm:ss+00:00".
    
    Args:
        time_str: string with a date
    Returns:
        boolean asserting if time_str formats as "YYYY-MM-DDThh:mm:ss+00:00"
    """
    try:
        test_time = datetime.strptime(time_str, "%Y-%m-%dT%H:%M:%S%z")
    except ValueError:
        return False
    # AR/SB it parses as an ISO string, now just check UTC timezone +00:00 and not +0000
    return time_str.endswith("+00:00")