code: def test_constant():
      x = np.arange(64).reshape((8, 8))
      d = da.from_array(x, chunks=(4, 4))
  
      e = constant(d, axis=0, depth=2, value=10)
      assert e.shape[0] == d.shape[0] + 4
      assert e.shape[1] == d.shape[1]
  
      assert_eq(e[1, :], np.ones(8, dtype=x.dtype) * 10)
      assert_eq(e[-1, :], np.ones(8, dtype=x.dtype) * 10)
  
imports: from __future__ import annotations
  import pytest
  import numpy
  from numpy.testing import assert_array_almost_equal, assert_array_equal
  import dask.array
  from dask.array.lib.stride_tricks import sliding_window_view
  from dask.array.overlap import boundaries, constant, ensure_minimum_chunksize, nearest, overlap, overlap_internal, periodic, reflect, trim_internal
  from dask.array.utils import assert_eq, same_keys
label_desc: Use image node_id 8 for calling a global function with example usage: test_constant() without return types