code: def transitions(self, year):
      start = self.start.year_to_epoch(year)
      end = self.end.year_to_epoch(year)
      return start, end
  
imports: import bisect
  import calendar
  import collections
  import functools
  import re
  import weakref
  from datetime import datetime, timedelta, tzinfo
  from .None import _common, _tzpath
label_desc: Use image node_id 2 for calling the _TZStr obj's underlying member method code with example usage: obj.transitions(year) and returns: start,  end