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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 result(self):
 """Return the value at an address, optionally waiting until it is set from the context_manager, or set based on the pre-fetch mechanism. Returns: (bytes):
 The opaque value for an address. """


        if self._read_only:
            return self._result
        with self._condition:
            if self._wait_for_tree and not self._result_set_in_context:
                self._condition.wait_for(
                    lambda: self._tree_has_set or self._result_set_in_context)
            return self._result