code: def count_nonzero(a, axis=None):
      """Counts the number of non-zero values in the array.
  
      .. note::
  
         :func:`numpy.count_nonzero` returns `int` value when `axis=None`,
         but :func:`cupy.count_nonzero` returns zero-dimensional array to reduce
         CPU-GPU synchronization.
  
      Args:
          a (cupy.ndarray): The array for which to count non-zeros.
          axis (int or tuple, optional): Axis or tuple of axes along which to
              count non-zeros. Default is None, meaning that non-zeros will be
              counted along a flattened version of ``a``
      Returns:
          cupy.ndarray of int: Number of non-zero values in the array
          along a given axis. Otherwise, the total number of non-zero values
          in the array is returned.
      """
  
      return _count_nonzero(a, axis=axis)
  
label_desc: Use image node_id 1 for calling a global function with example usage: count_nonzero(a, axis) and returns: _count_nonzero