code: def __iter__(self):
      for n in range(1, self.n):
          for m in range(1, self.m):
              yield n, m
  
imports: import array
  from abc import ABC, abstractmethod
  from itertools import repeat
  from typing import Tuple
  import numpy
  from .window import CRWindow, Window
label_desc: Use image node_id 3 for calling the DenseCostMatrix obj's underlying member method code with example usage: obj.__iter__() without return types