langchain/text_splitter.py/RecursiveCharacterTextSplitter/__init__
class RecursiveCharacterTextSplitter:    def __init__(
        self,
        separators: Optional[List[str]] = None,
        keep_separator: bool = True,
        **kwargs: Any,
    ):
        """Create a new TextSplitter."""
        super().__init__(keep_separator=keep_separator, **kwargs)
        self._separators = separators or ["\n\n", "\n", " ", ""]