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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 is_partial(self, filename):
 """Check if a file is a partial. Partial files are not rendered, but they are used in rendering templates. A file is considered a partial if it or any of its parent directories are prefixed with an ``'_'``. :param filename: the name of the file to check """

        return any((x.startswith("_") for x in filename.split(os.path.sep)))