code: def slice_indices(slice, length):
      """
      Reference implementation for the slice.indices method.
  
      """
      # Compute step and length as integers.
      length = operator.index(length)
      step = (
          1 if slice.step is None else evaluate_slice_index(slice.step)
      )
  
      # Raise ValueError for negative length or zero step.
      if length < 0:
          raise ValueError("length should not be negative")
      if step == 0:
          raise ValueError("slice step cannot be zero")
  
      # Find lower and upper bounds for start and stop.
      lower = -1 if step < 0 else 0
      upper = length - 1 if step < 0 else length
  
      # Compute start.
      if slice.start is None:
          start = upper if step < 0 else lower
      else:
          start = evaluate_slice_index(slice.start)
          start = (
              max(start + length, lower)
              if start < 0
              else min(start, upper)
          )
  
      # Compute stop.
      if slice.stop is None:
          stop = lower if step < 0 else upper
      else:
          stop = evaluate_slice_index(slice.stop)
          stop = (
              max(stop + length, lower)
              if stop < 0
              else min(stop, upper)
          )
  
      return start, stop, step
  
imports: import itertools
  import operator
  import sys
  import unittest
  import weakref
  import copy
  from pickle import loads, dumps
  from test import support
label_desc: Use image node_id 2 for calling a global function with example usage: slice_indices(slice, length) and returns: start,  stop,  step