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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 private_dir_path(app_name):
 """Returns the private directory path :param str app_name: the name of the app :rtype: str :returns: directory path """

    _private_dir_path = os.path.expanduser(click.get_app_dir(
        app_name,
        force_posix=True,  # forces to ~/.tigerhost on Mac and Unix
    ))
    return _private_dir_path