class_docstr: Collect data by size and step.
class_docstr_tok: ["Collect","data","by","size","and","step","."]
code: def __init__(self, size: int, step: int, start_index: int = 0):
      self._start_index = start_index
      self._end_index = start_index + size
      self._next_start_index = start_index + step
      self._size = size
      self._step = step
      self._buffer = []
      self._next_buffer = None
  
file_path: towhee/towhee/runtime/nodes/_window.py
imports: from typing import List
  from towhee.runtime.constants import WindowConst
  from ._window_base import WindowBase
label_desc: Use image node_id 1 to create a new _WindowBuffer object  with example: obj = _WindowBuffer(size, step, start_index)