Set the result of the future to the provided result.

        Args:
            result (Any): The result

def set_result(self, result):
        """Set the result of the future to the provided result.

        Args:
            result (Any): The result
        """
        # Sanity check: A future can only complete once.
        if self.done():
            raise RuntimeError("set_result can only be called once.")

        # Set the result and trigger the future.
        self._result = result
        self._trigger()