class_docstr: A WindowAssigner that windows elements into fixed-size windows based on the timestamp of
  the elements. Windows cannot overlap.
class_docstr_tok: ["A","WindowAssigner","that","windows","elements","into","fixed-size","windows","based","on","the","timestamp","of","the","elements",".","Windows","can","not","overlap","."]
code: def is_event_time(self) -> bool:
      return self._is_event_time
  
imports: import math
  from abc import ABC, abstractmethod
  from typing import Generic, List, Any, Iterable, Set
  from pyflink.common.typeinfo import Types
  from pyflink.datastream.state import ValueStateDescriptor, ValueState
  from pyflink.datastream.window import TimeWindow, CountWindow
  from pyflink.fn_execution.table.window_context import Context, W
label_desc: Use image node_id 3 for calling the TumblingWindowAssigner obj's underlying member method code with example usage: obj.is_event_time() and returns: self