How to use the isodate.UTC function in isodate

def test_expired():
    # valid
    expiration = dt.utcnow() + timedelta(seconds=10)
    expiration = expiration.replace(tzinfo=isodate.UTC)
    expiration = isodate.strftime(expiration, isodate.DT_EXT_COMPLETE)
    agent = Agent(expiration=expiration)
    admin = agent.Admin()
    print admin.echo('FUTURE')
    # invalid
    agent = Agent(expiration='12345')
    admin = agent.Admin()
    print admin.echo('INVALID')
    # expired
    expiration = dt.utcnow() - timedelta(seconds=10)
    expiration = expiration.replace(tzinfo=isodate.UTC)
    expiration = isodate.strftime(expiration, isodate.DT_EXT_COMPLETE)
    agent = Agent(wait=0, expiration=expiration)
    admin = agent.Admin()
    print admin.echo('EXPIRED')
    sys.exit(0)

def executePost(self, db=True):
        if self.procedurename is None:
            raise Exception(
                "POST action without procedure name not allowed")

        from datetime import datetime
        now = datetime.now(iso.UTC)
        non_blocking_exceptions = []

	    # path to file for logging requests
        dir_name = os.path.dirname(__file__)
        file_name = os.path.join(dir_name, 'logs', 'fast_insert_log.csv')

        # Create data array
        data = self.waEnviron['wsgi_input'].decode().split(";")
        data_log = data[:]

        # Assigned id always in the first position
        assignedid = data[0]

        if len(data) == 4:  # regular time series
            mode = self.MODE_REGULAR

def utc_tz():
    """
    Get the UTC timezone.
    @rtype: datetime.tzinfo instance
    @return: a tzinfo instance representing the utc timezone
    """
    return isodate.UTC

def utc_tz():
    """
    Get the UTC timezone.
    @rtype: datetime.tzinfo instance
    @return: a tzinfo instance representing the utc timezone
    """
    return isodate.UTC

def utc_tz():
    """
    Get the UTC timezone.
    @rtype: datetime.tzinfo instance
    @return: a tzinfo instance representing the utc timezone
    """
    return isodate.UTC

self.last_updated = last_updated or time.time()
        self.name = id
        self.options = options or {}
        self.principal = principal
        self.resource = resource
        self.schedule = schedule
        self.task = task
        self.total_run_count = total_run_count
        self.kwargs['scheduled_call_id'] = self.id

        if first_run is None:
            # get the date and time from the iso_schedule value, and if it does not have a date and
            # time, use the current date and time
            self.first_run = dateutils.format_iso8601_datetime(
                dateutils.parse_iso8601_interval(iso_schedule)[1] or
                datetime.utcnow().replace(tzinfo=isodate.UTC))
        elif isinstance(first_run, datetime):
            self.first_run = dateutils.format_iso8601_datetime(first_run)
        else:
            self.first_run = first_run
        if remaining_runs is None:
            self.remaining_runs = dateutils.parse_iso8601_interval(iso_schedule)[2]
        else:
            self.remaining_runs = remaining_runs

        self.next_run = self.calculate_next_run()

for importer in collection.find():
        modified = False

        if config_key not in importer:
            importer[config_key] = {}
            modified = True

        # If the key doesn't exist, or does exist but has no value, set it based on the
        # last sync time, if possible. Otherwise, set it to now.
        if not importer.get(updated_key, None):
            try:
                importer[updated_key] = isodate.parse_datetime(importer['last_sync'])
            # The attribute doesn't exist, or parsing failed. It's safe to set a newer timestamp.
            except:  # noqa: 722
                importer[updated_key] = datetime.datetime.now(tz=isodate.UTC)
            modified = True

        if modified:
            collection.save(importer)