code: def generate_binary_structure(rank, connectivity):
      """Generate a binary structure for binary morphological operations.
  
      Args:
          rank(int): Number of dimensions of the array to which the structuring
              element will be applied, as returned by ``np.ndim``.
          connectivity(int): ``connectivity`` determines which elements of the
              output array belong to the structure, i.e., are considered as
              neighbors of the central element. Elements up to a squared distance
              of ``connectivity`` from the center are considered neighbors.
              ``connectivity`` may range from 1 (no diagonal elements are
              neighbors) to ``rank`` (all elements are neighbors).
  
      Returns:
          cupy.ndarray: Structuring element which may be used for binary
          morphological operations, with ``rank`` dimensions and all
          dimensions equal to 3.
  
      .. seealso:: :func:`scipy.ndimage.generate_binary_structure`
      """
      if connectivity < 1:
          connectivity = 1
      if rank < 1:
          return cupy.asarray(True, dtype=bool)
      output = numpy.fabs(numpy.indices([3] * rank) - 1)
      output = numpy.add.reduce(output, 0)
      output = output <= connectivity
      return cupy.asarray(output)
  
imports: import operator
  import warnings
  import numpy
  import cupy
  from cupy import _core
  from cupyx.scipy.ndimage import _filters_core
  from cupyx.scipy.ndimage import _util
  from cupyx.scipy.ndimage import _filters
label_desc: Use image node_id 4 for calling a global function with example usage: generate_binary_structure(rank, connectivity) and returns: cupy, cupy