def extract_utc_timestamp_from_log_line(line):
    # Extract ISO 8601 date per http://www.pelagodesign.com/blog/2009/05/20/iso-8601-date-validation-that-doesnt-suck/
    iso_re = r'^([\+-]?\d{4}(?!\d{2}\b))((-?)((0[1-9]|1[0-2])(\3([12]\d|0[1-9]|3[01]))?|W([0-4]\d|5[0-2])(-?[1-7])?|' \
        r'(00[1-9]|0[1-9]\d|[12]\d{2}|3([0-5]\d|6[1-6])))([T\s]((([01]\d|2[0-3])((:?)[0-5]\d)?|24\:?00)([\.,]\d+' \
        r'(?!:))?)?(\17[0-5]\d([\.,]\d+)?)?([zZ]|([\+-])([01]\d|2[0-3]):?([0-5]\d)?)?)?)? '

    tokens = re.match(iso_re, line)

    if not tokens:
        # Could not parse line
        return None
    timestamp = tokens.group(0).strip()
    dt = isodate.parse_datetime(timestamp)
    utc_timestamp = datetime_convert_timezone(dt, dt.tzinfo, dateutil.tz.tzutc())
    return utc_timestamp
Asserts that val is an existing path to a file.
dataset/ETHPy150Open Yelp/paasta/paasta_tools/cli/cmds/logs.py/extract_utc_timestamp_from_log_line--crossover with--dataset/ETHPy150Open ActivisionGameScience/assertpy/assertpy/assertpy.py/AssertionBuilder.is_file