code: def test_slicers2segments():
      # Test function to construct segments from slice objects
      assert slicers2segments((0,), (10,), 7, 4) == [[7, 4]]
      assert slicers2segments((0, 1), (10, 6), 7, 4) == [
          [7 + 10 * 4, 4]
      ]
      assert slicers2segments((0, 1, 2), (10, 6, 4), 7, 4) == [
          [7 + 10 * 4 + 10 * 6 * 2 * 4, 4]
      ]
      assert slicers2segments((slice(None),), (10,), 7, 4) == [
          [7, 10 * 4]
      ]
      assert slicers2segments((0, slice(None)), (10, 6), 7, 4) == [
          [7 + 10 * 4 * i, 4] for i in range(6)
      ]
      assert slicers2segments((slice(None), 0), (10, 6), 7, 4) == [
          [7, 10 * 4]
      ]
      assert slicers2segments(
          (slice(None), slice(None)), (10, 6), 7, 4
      ) == [[7, 10 * 6 * 4]]
      assert slicers2segments(
          (slice(None), slice(None), 2), (10, 6, 4), 7, 4
      ) == [[7 + 10 * 6 * 2 * 4, 10 * 6 * 4]]
  
imports: import time
  from functools import partial
  from io import BytesIO
  from itertools import product
  from threading import Lock, Thread
  import numpy
  import pytest
  from numpy.testing import assert_array_equal
  from ..fileslice import _positive_slice, _simple_fileslice, calc_slicedefs, canonical_slicers, fileslice, fill_slicer, is_fancy, optimize_read_slicers, optimize_slicer, predict_shape, read_segments, slice2len, slice2outax, slicers2segments, strided_scalar, threshold_heuristic
label_desc: Use image node_id 15 for calling a global function with example usage: test_slicers2segments() without return types