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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 _make_cookie(self):
 """ Return a string encoding the ID of the process, instance and thread. This disambiguates legitimate wake-ups, accidental writes to the FD, and buggy internal FD sharing. """

        return struct.pack(self.COOKIE_FMT, self.COOKIE_MAGIC,
                           os.getpid(), id(self), thread.get_ident())