code: def flipud(m):
      """
      Flip tensor in the up/down direction.
  
      Flip the entries in each column in the up/down direction.
      Rows are preserved, but appear in a different order than before.
  
      Parameters
      ----------
      m : array_like
          Input tensor.
  
      Returns
      -------
      out : array_like
          A view of `m` with the rows reversed.  Since a view is
          returned, this operation is :math:`\\mathcal O(1)`.
  
      See Also
      --------
      fliplr : Flip tensor in the left/right direction.
      rot90 : Rotate tensor counterclockwise.
  
      Notes
      -----
      Equivalent to ``m[::-1,...]``.
      Does not require the tensor to be two-dimensional.
  
      Examples
      --------
      >>> import mars.tensor as mt
  
      >>> A = mt.diag([1.0, 2, 3])
      >>> A.execute()
      array([[ 1.,  0.,  0.],
             [ 0.,  2.,  0.],
             [ 0.,  0.,  3.]])
      >>> mt.flipud(A).execute()
      array([[ 0.,  0.,  3.],
             [ 0.,  2.,  0.],
             [ 1.,  0.,  0.]])
  
      >>> A = mt.random.randn(2,3,5)
      >>> mt.all(mt.flipud(A) == A[::-1,...]).execute()
      True
  
      >>> mt.flipud([1,2]).execute()
      array([2, 1])
  
      """
      return flip(m, 0)
  
label_desc: Use image node_id 1 for calling a global function with example usage: flipud(m) and returns: flip