from datetime import datetime


def parse_millisecond_time(time_str):
    """
    Parses the timestamp string to a datetime object. The timestamp string should fit the format
    yyyy-MM-dd'T'HH:mm:ss.SSSZ
    """
    # remove timezone info
    time_str = time_str[:-5]
    return datetime.strptime(time_str, '%Y-%m-%dT%H:%M:%S.%f')