code: def compress_by_chunk(self, cupy_bool_tensor, num_chunks):
      packed_sign = cupy.packbits(cupy_bool_tensor)
      sign_list_packed = cupy.split(packed_sign, num_chunks)
      cupy.cuda.get_current_stream().synchronize()
      return sign_list_packed
  
file_path: deepspeed/deepspeed/runtime/compression/cupy.py
imports: import cupy
  from torch.utils.dlpack import to_dlpack
  from torch.utils.dlpack import from_dlpack
label_desc: Use image node_id 4 for calling the CupyBackend obj's underlying member method code with example usage: obj.compress_by_chunk(cupy_bool_tensor, num_chunks) and returns: sign_list_packed