class_docstr: The implementation of InternalWindowProcessFunction for MergingWindowAssigner.
class_docstr_tok: ["The","implementation","of","InternalWindowProcessFunction","for","MergingWindowAssigner","."]
code: def assign_state_namespace(
      self, input_row: List, timestamp: int
  ) -> List[W]:
      element_windows = self._window_assigner.assign_windows(
          input_row, timestamp
      )
      self._initialize_cache(self._ctx.current_key())
      self._reuse_actual_windows = []
      for window in element_windows:
          # adding the new window might result in a merge, in that case the actualWindow
          # is the merged window and we work with that. If we don't merge then
          # actualWindow == window
          actual_window = self._add_window(window)
  
          # drop if the window is already late
          if self.is_window_late(actual_window):
              self._window_mapping.remove(actual_window)
              self._sorted_windows.remove(actual_window)
          else:
              self._reuse_actual_windows.append(actual_window)
  
      affected_windows = [
          self._window_mapping.get(actual)
          for actual in self._reuse_actual_windows
      ]
      return affected_windows
  
imports: from abc import abstractmethod, ABC
  from typing import Generic, List, Iterable, Dict, Set
  from pyflink.common import Row
  from pyflink.common.constants import MAX_LONG_VALUE
  from pyflink.datastream.state import MapState
  from pyflink.fn_execution.table.window_assigner import WindowAssigner, PanedWindowAssigner, MergingWindowAssigner
  from pyflink.fn_execution.table.window_context import Context, K, W
label_desc: Use image node_id 3 for calling the MergingWindowProcessFunction obj's underlying member method code with example usage: obj.assign_state_namespace(input_row, timestamp) and returns: affected_windows