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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 newer(self, source, target):
 """Tell if the target is newer than the source. Returns true if 'source' exists and is more recently modified than 'target', or if 'source' exists and 'target' doesn't. Returns false if both exist and 'target' is the same age or younger than 'source'. Raise PackagingFileError if 'source' does not exist. Note that this test is not very accurate: files created in the same second will have the same "age". """

        if not os.path.exists(source):
            raise DistlibException("file '%r' does not exist" %
                                   os.path.abspath(source))
        if not os.path.exists(target):
            return True

        return os.stat(source).st_mtime > os.stat(target).st_mtime