code: def __init__(self, queue, block_size):
      self.queue = queue
      mf = cl.mem_flags
      self.dev_buf_1 = cl.Buffer(
          queue.context, mf.READ_WRITE, block_size
      )
      self.dev_buf_2 = cl.Buffer(
          queue.context, mf.READ_WRITE, block_size
      )
  
imports: import pyopencl
  import numpy
label_desc: Use image node_id 1 to create a new DeviceToDeviceTransfer object  with example: obj = DeviceToDeviceTransfer(queue, block_size)