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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 msetnx(self, key, value, *pairs):
 """Set multiple keys to multiple values, only if none of the keys exist. :raises TypeError: if len of pairs is not event number """

        if len(pairs) % 2 != 0:
            raise TypeError("length of pairs must be even number")
        return self.execute(b'MSETNX', key, value, *pairs)