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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 utime(self, tarinfo, targetpath):
 """Set modification time of targetpath according to tarinfo. """

        if not hasattr(os, 'utime'):
            return
        try:
            os.utime(targetpath, (tarinfo.mtime, tarinfo.mtime))
        except EnvironmentError as e:
            raise ExtractError("could not change modification time")