Converts datetime isoformat string to datetime (dt) object

    Args:
        :dt_str (str): input string in '2017-12-30T18:48:00.353Z' form
         or similar
    Returns:
        TYPE:  datetime object

def convert_strtime_datetime(dt_str):
    """ Converts datetime isoformat string to datetime (dt) object

    Args:
        :dt_str (str): input string in '2017-12-30T18:48:00.353Z' form
         or similar
    Returns:
        TYPE:  datetime object
    """
    dt, _, us = dt_str.partition(".")
    dt = datetime.datetime.strptime(dt, "%Y-%m-%dT%H:%M:%S")
    us = int(us.rstrip("Z"), 10)
    return dt + datetime.timedelta(microseconds=us)