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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 recover(self, key, value):
 """Get the deserialized value for a given key, and the serialized version."""

        if key not in self._dtypes:
            self.read_types()
        if key not in self._dtypes:
            raise ValueError("Unknown datatype for {} and {}".format(key, value))
        return self._dtypes[key][2](value)