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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 out_of_date(original, derived):
 """ Returns True if derivative is out-of-date wrt original, both of which are full file paths. """

    return (not os.path.exists(derived)
            or os.stat(derived).st_mtime < os.stat(original).st_mtime)