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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 psetex(self, key, milliseconds, value):
 """Set the value and expiration in milliseconds of a key. :raises TypeError: if milliseconds is not int """

        if not isinstance(milliseconds, int):
            raise TypeError("milliseconds argument must be int")
        fut = self.execute(b'PSETEX', key, milliseconds, value)
        return wait_ok(fut)