code: def triu(m, k=0):
      """
      Upper triangle of an array.
  
      Return a copy of a matrix with the elements below the `k`-th diagonal
      zeroed.
  
      Please refer to the documentation for `tril` for further details.
  
      See Also
      --------
      tril : lower triangle of an array
  
      Examples
      --------
      >>> np.triu([[1,2,3],[4,5,6],[7,8,9],[10,11,12]], -1)
      array([[ 1,  2,  3],
             [ 4,  5,  6],
             [ 0,  8,  9],
             [ 0,  0, 12]])
  
      """
      m = asanyarray(m)
      mask = tri(*m.shape[-2:], k=k - 1, dtype=bool)
  
      return where(mask, zeros(1, m.dtype), m)
  
imports: from __future__ import division, absolute_import, print_function
  import functools
  from numpy.core.numeric import absolute, asanyarray, arange, zeros, greater_equal, multiply, ones, asarray, where, int8, int16, int32, int64, empty, promote_types, diagonal, nonzero
  from numpy.core.overrides import set_module
  from numpy.core import overrides
  from numpy.core import iinfo, transpose
label_desc: Use image node_id 12 for calling a global function with example usage: triu(m, k) and returns: where