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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 getrange(self, key, start, end, *, encoding=_NOTSET):
 """Get a substring of the string stored at a key. :raises TypeError: if start or end is not int """

        if not isinstance(start, int):
            raise TypeError("start argument must be int")
        if not isinstance(end, int):
            raise TypeError("end argument must be int")
        return self.execute(b'GETRANGE', key, start, end, encoding=encoding)