docstr: Return the offset in the write stream of the first byte in the
  write buffer.
docstr_tok: ["Return","the","offset","in","the","write","stream","of","the","first","byte","in","the","write","buffer","."]
code: def offset(self) -> int:
      """Return the offset in the write stream of the first byte in the
      write buffer."""
      return self._offset
  
file_path: hail/hail/python/hailtop/aiotools/utils.py
imports: from typing import Deque, TypeVar, AsyncIterator, Iterator
  import collections
  from contextlib import contextmanager
  import asyncio
label_desc: Use image node_id 4 for calling the WriteBuffer obj's underlying member method code with example usage: obj.offset() and returns: self