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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 get_koji_upload_dir():
 """ Create a path name for uploading files to :return: str, path name expected to be unique """

        dir_prefix = 'koji-upload'
        random_chars = ''.join([random.choice(ascii_letters)
                                for _ in range(8)])
        unique_fragment = '%r.%s' % (time.time(), random_chars)
        return os.path.join(dir_prefix, unique_fragment)