code: def __contains__(self, item):
      if self._cache_complete:
          return item in self._cache
      else:
          for i in self:
              if i == item:
                  return True
              elif i > item:
                  return False
      return False
  
imports: import calendar
  import datetime
  import heapq
  import itertools
  import re
  import sys
  from functools import wraps
  from warnings import warn
  from six import advance_iterator, integer_types
  from six.moves import _thread, range
  from ._common import weekday
label_desc: Use image node_id 6 for calling the rrulebase obj's underlying member method code with example usage: obj.__contains__(item) and returns: False, unknown, True, False