code: def __init__(self, thread_pool: ThreadPoolExecutor, f: BinaryIO):
      super().__init__()
      self._thread_pool = thread_pool
      self._f = f
      self._start = f.tell()
  
imports: from typing import BinaryIO, List, Optional, Tuple, Type
  from types import TracebackType
  import abc
  import io
  import os
  import sys
  from concurrent.futures import ThreadPoolExecutor
  import janus
  from hailtop.utils import blocking_to_async
  from .exceptions import UnexpectedEOFError
label_desc: Use image node_id 1 to create a new _WritableStreamFromBlocking object from inherited base classes: WritableStream with example: obj = _WritableStreamFromBlocking(thread_pool, f)