def get_value(self, node):
        """Convert value from an AST node."""
        if not isinstance(node, ast.Dict):
            raise TypeError("must be a dictionary")

        evaluator = SafeEvaluator()
        try:
            value = evaluator.run(node)
        except Exception as ex:
            # TODO: Handle errors.
            raise ex

        try:
            # Ensure value is a serializable dictionary.
            value = json.loads(json.dumps(value))
            if not isinstance(value, dict):
                raise TypeError
        except (TypeError, ValueError):
            raise TypeError("must be serializable")

        return value
Convert value from an AST node.