class_docstr: Binary datasource, for reading and writing binary files.
code: def _rows_per_file(self):
      return 1
  
file_path: ray/python/ray/data/datasource/binary_datasource.py
imports: from typing import TYPE_CHECKING
  from ray.data._internal.arrow_block import ArrowBlockBuilder
  from ray.data.datasource.file_based_datasource import FileBasedDatasource
  from ray.util.annotations import PublicAPI
label_desc: Use image node_id 2 for calling the BinaryDatasource obj's underlying member method code with example usage: obj._rows_per_file() and returns: int