def get_reader_type(reader: str) -> str:
    """
    Return loader type among, file, dir or in-memory.

    Args:
        loader (str): Name of the loader, whose type is to be resolved.

    Returns:
        str: One of the loader type among, file/dir/in-memory.

    """
    for reader_type, readers in READER_TYPE_MAPPING.items():
        if reader in readers:
            return reader_type
    return "unknown"

    Return loader type among, file, dir or in-memory.

    Args:
        loader (str): Name of the loader, whose type is to be resolved.

    Returns:
        str: One of the loader type among, file/dir/in-memory.

    
llama-index-integrations/readers/llama-index-readers-pebblo/llama_index/readers/pebblo/utility.py