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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 isdir(path, message):
 """ Raise an exception if the given directory does not exist. :param path: The path to a directory to be tested :param message: A custom message to report in the exception :raises: FileNotFoundError """

    if not os.path.isdir(path):
        raise FileNotFoundError(
            errno.ENOENT,
            "{}: {}".format(message, os.strerror(errno.ENOENT)), path)