@Override
        public Void visitMultiSelectHash(MultiSelectHashExpression expression) {
            // e.g.: {foo: `true`, bar: bar}
            builder.append('{');
            int i = 0;
            for (Map.Entry<String, JmespathExpression> entry : expression.getExpressions().entrySet()) {
                builder.append('"').append(sanitizeString(entry.getKey(), false)).append("\": ");
                entry.getValue().accept(this);
                if (i < expression.getExpressions().entrySet().size() - 1) {
                    builder.append(", ");
                }
                i++;
            }
            builder.append('}');
            return null;
        }
Serialize the given JMESPath expression to a string.

@param expression JMESPath expression to serialize.
@return Returns the serialized expression.
smithy-jmespath/src/main/java/software/amazon/smithy/jmespath/ExpressionSerializer.java