code: def _find_delimiter(f, block_size=2**16):
      delimiter = b"\n"
      if f.tell() == 0:
          return 0
      while True:
          b = f.read(block_size)
          if not b:
              return f.tell()
          elif delimiter in b:
              return f.tell() - len(b) + b.index(delimiter) + 1
  
imports: from io import BytesIO
  from urllib.parse import urlparse
  import pandas
  import numpy
  from ...None import opcodes
  from ...config import options
  from ...core import OutputType
  from ...lib.filesystem import get_fs, open_file, file_size, glob
  from ...serialization.serializables import StringField, DictField, ListField, Int32Field, Int64Field, BoolField, AnyField
  from ...utils import parse_readable_size, lazy_import, FixedSizeFileObject
  from ..arrays import ArrowStringDtype
  from ..utils import parse_index, build_empty_df, to_arrow_dtypes, contain_arrow_dtype
  from .core import IncrementalIndexDatasource, ColumnPruneSupportedDataSourceMixin, IncrementalIndexDataSourceMixin, merge_small_files
label_desc: Use image node_id 1 for calling a global function with example usage: _find_delimiter(f, block_size) and returns: int, f, unknown