code: def _set_batch_non_diagonal_cpu(array, non_diag_val):
      batch_size, m, n = array.shape
      assert m == n
      rows, cols = np.tril_indices(n, -1)
      array[:, rows, cols] = non_diag_val
  
imports: from functools import lru_cache
  from chainer import cuda
  from chainer import function
  from chainer.utils import type_check
  import numpy
label_desc: Use image node_id 10 for calling a global function with example usage: _set_batch_non_diagonal_cpu(array, non_diag_val) without return types