code: def _pattern_of(index):
      """
      Return the pattern represented by an index value
      Byte decomposition of index
      """
      return np.array(
          [
              [index & 2**0, index & 2**1, index & 2**2],
              [index & 2**3, index & 2**4, index & 2**5],
              [index & 2**6, index & 2**7, index & 2**8],
          ],
          bool,
      )
  
file_path: scikit-image/skimage/morphology/_skeletonize.py
imports: import numpy
  from scipy import ndimage
  from .._shared.utils import check_nD
  from ..util import crop
  from ._skeletonize_3d_cy import _compute_thin_image
  from ._skeletonize_cy import _fast_skeletonize, _skeletonize_loop, _table_lookup_index
label_desc: Use image node_id 6 for calling a global function with example usage: _pattern_of(index) and returns: np