code: def extract(self, element: tuple) -> int:
      return element[1]
  
file_path: flink/flink-python/pyflink/examples/datastream/windowing/session_with_dynamic_gap_window.py
imports: import sys
  import argparse
  from typing import Iterable
  from pyflink.datastream.connectors.file_system import FileSink, OutputFileConfig, RollingPolicy
  from pyflink.common import Types, WatermarkStrategy, Encoder
  from pyflink.common.watermark_strategy import TimestampAssigner
  from pyflink.datastream import StreamExecutionEnvironment, ProcessWindowFunction
  from pyflink.datastream.window import EventTimeSessionWindows, SessionWindowTimeGapExtractor, TimeWindow
label_desc: Use image node_id 1 for calling the MySessionWindowTimeGapExtractor obj's underlying member method code with example usage: obj.extract(element) and returns: element