How to use the pywws.weatherstation.WSDateTime.from_csv function in pywws

self.params = context.params
        self.status = context.status
        self.raw_data = context.raw_data
        # connect to weather station
        self.ws = WeatherStation(context=context)
        # check computer clock isn't earlier than last stored data
        self.last_stored_time = self.raw_data.before(datetime.max) or datetime.min
        if datetime.utcnow() < self.last_stored_time:
            raise ValueError('Computer time is earlier than last stored data')
        # infer pointer of last stored data
        saved_ptr = self.status.get('data', 'ptr')
        if saved_ptr:
            saved_ptr, sep, saved_date = saved_ptr.partition(',')
            if saved_ptr and saved_date:
                saved_ptr = int(saved_ptr, 16)
                saved_date = WSDateTime.from_csv(saved_date)
                saved_date = self.raw_data.nearest(saved_date)
                while saved_date < self.last_stored_time:
                    saved_date = self.raw_data.after(saved_date + SECOND)
                    saved_ptr = self.ws.inc_ptr(saved_ptr)
                while saved_date > self.last_stored_time:
                    saved_date = self.raw_data.before(saved_date - SECOND)
                    saved_ptr = self.ws.dec_ptr(saved_ptr)
            else:
                saved_ptr = None
        self.last_stored_ptr = saved_ptr
        self.check_fixed_block()

else:
                        round_time = None
                elif command[0] == 'jump':
                    prevdata = data
                    idx, valid_data = jump(idx, int(command[1]))
                    data = data_set[idx]
                elif command[0] == 'goto':
                    prevdata = data
                    time_str = command[1]
                    if '%' in time_str:
                        if local_time:
                            lcl = timezone.to_local(idx)
                        else:
                            lcl = timezone.to_utc(idx)
                        time_str = lcl.strftime(time_str)
                    new_idx = pywws.weatherstation.WSDateTime.from_csv(time_str)
                    if local_time:
                        new_idx = timezone.to_naive(timezone.localize(new_idx))
                    new_idx = data_set.after(new_idx)
                    if new_idx:
                        idx = new_idx
                        data = data_set[idx]
                        valid_data = True
                    else:
                        valid_data = False
                elif command[0] == 'loop':
                    loop_count = int(command[1])
                    loop_start = tmplt.tell()
                elif command[0] == 'endloop':
                    loop_count -= 1
                    if valid_data and loop_count > 0:
                        tmplt.seek(loop_start, 0)

def get_datetime(self, section, option, default=None):
        result = self.get(section, option, default)
        if result:
            return WSDateTime.from_csv(result)
        return result

'wind_gust'            : float,
        'wind_gust_t'          : WSDateTime.from_csv,
        'wind_dir'             : float,
        'rain'                 : float,
        'rain_days'            : int,
        'illuminance_ave'      : float,
        'illuminance_max_lo'   : float,
        'illuminance_max_lo_t' : WSDateTime.from_csv,
        'illuminance_max_hi'   : float,
        'illuminance_max_hi_t' : WSDateTime.from_csv,
        'illuminance_max_ave'  : float,
        'uv_ave'               : float,
        'uv_max_lo'            : int,
        'uv_max_lo_t'          : WSDateTime.from_csv,
        'uv_max_hi'            : int,
        'uv_max_hi_t'          : WSDateTime.from_csv,
        'uv_max_ave'           : float,
        }

    def _get_cache_path(self, target_date):
        # one file per year
        path = os.path.join(self._root_dir,
                            target_date.strftime("%Y-01-01.txt"))
        lo = target_date.replace(month=1, day=1)
        if lo.year < MAXYEAR:
            hi = lo.replace(year=lo.year+1)
        else:
            hi = lo
            lo = hi.replace(year=hi.year-1)
        return path, lo, hi