code: def setUpClass(cls):
      super(StatelessRulesTests, cls).setUpClass()
  
      cls.class_ = StatelessRule
      cls.cal = get_calendar(cls.CALENDAR_STRING)
  
      # First day of 09/2014 is closed whereas that for 10/2014 is open
      cls.sept_sessions = cls.cal.sessions_in_range(
          pd.Timestamp("2014-09-01", tz="UTC"),
          pd.Timestamp("2014-09-30", tz="UTC"),
      )
      cls.oct_sessions = cls.cal.sessions_in_range(
          pd.Timestamp("2014-10-01", tz="UTC"),
          pd.Timestamp("2014-10-31", tz="UTC"),
      )
  
      cls.sept_week = cls.cal.minutes_for_sessions_in_range(
          pd.Timestamp("2014-09-22", tz="UTC"),
          pd.Timestamp("2014-09-26", tz="UTC"),
      )
  
      cls.HALF_SESSION = None
      cls.FULL_SESSION = None
  
imports: import datetime
  from inspect import isabstract
  import random
  from unittest import TestCase
  import warnings
  from nose_parameterized import parameterized
  import pandas
  from six import iteritems
  from six.moves import range, map
  import catalyst.utils.events
  from catalyst.utils.calendars import get_calendar
  from catalyst.utils.events import EventRule, StatelessRule, Always, Never, AfterOpen, ComposedRule, BeforeClose, NotHalfDay, NthTradingDayOfWeek, NDaysBeforeLastTradingDayOfWeek, NthTradingDayOfMonth, NDaysBeforeLastTradingDayOfMonth, StatefulRule, OncePerDay, _build_offset, _build_date, _build_time, EventManager, Event, MAX_MONTH_RANGE, MAX_WEEK_RANGE, TradingDayOfMonthRule, TradingDayOfWeekRule
label_desc: Use image node_id 1 for calling the StatelessRulesTests obj's underlying member method code with example usage: obj.setUpClass(cls) without return types