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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 lset(self, key, index, value):
 """Sets the list element at index to value. :raises TypeError: if index is not int """

        if not isinstance(index, int):
            raise TypeError("index argument must be int")
        return self.execute(b'LSET', key, index, value)