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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def __ensure_directory_in_path(filename: Path) -> None: """Ensures that a file's directory is in the Python path. """

    directory = Path(filename).parent.resolve()
    if directory not in sys.path:
        logger.debug(f"Adding {directory} to sys.path")
        sys.path.insert(0, str(directory))