如何在mule中找到两个时间戳值之间的差异？

<mule xmlns:dw="http://www.mulesoft.org/schema/mule/ee/dw" xmlns:ee="http://www.mulesoft.org/schema/mule/ee/core"
    xmlns:http="http://www.mulesoft.org/schema/mule/http" xmlns="http://www.mulesoft.org/schema/mule/core"
    xmlns:doc="http://www.mulesoft.org/schema/mule/documentation" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd
        http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
        http://www.mulesoft.org/schema/mule/ee/core http://www.mulesoft.org/schema/mule/ee/core/current/mule-ee.xsd
        http://www.mulesoft.org/schema/mule/ee/dw http://www.mulesoft.org/schema/mule/ee/dw/current/dw.xsd">
    <http:listener-config name="HTTP_Listener_config" doc:name="HTTP Listener config" doc:id="f3a6f7f7-7e0a-4a5e-8a2f-3e4e1b3e7d0e" >
        <http:listener-connection host="0.0.0.0" port="8081" />
    </http:listener-config>
    <flow name="time-difference-flow" doc:id="c1a7e6b7-5e0a-4e7b-9e5a-6f4e1b3e7d0e">
        <http:listener doc:name="Listener" doc:id="a1a7e6b7-5e0a-4e7b-9e5a-6f4e1b3e7d0e" config-ref="HTTP_Listener_config" path="/difference" />
        <ee:transform doc:name="Transform Message" doc:id="b1a7e6b7-5e0a-4e7b-9e5a-6f4e1b3e7d0e">
            <ee:message>
                <ee:set-payload><![CDATA[%dw 2.0
output application/json
---
{
    "timestamp1": "2022-01-01T00:00:00Z",
    "timestamp2": "2022-01-02T00:00:00Z"
}]]></ee:set-payload>
            </ee:message>
        </ee:transform>
        <dw:transform-message doc:name="Transform Message" doc:id="d1a7e6b7-5e0a-4e7b-9e5a-6f4e1b3e7d0e">
            <dw:set-payload><![CDATA[%dw 2.0
output application/json
---
{
    "difference": (|
        now() as LocalDateTime - (payload.timestamp1 as LocalDateTime),
        now() as LocalDateTime - (payload.timestamp2 as LocalDateTime)
    )
}]]></dw:set-payload>
        </dw:transform-message>
    </flow>
</mule>