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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 _hashed_key(self):
 """ Returns 16-digit numeric hash of the redis key """

        return abs(int(hashlib.md5(
            self.key_prefix.encode('utf8')
        ).hexdigest(), 16)) % (10 ** (
            self._size_mod if hasattr(self, '_size_mod') else 5))