converting date from a timezone to UTC XSLT 1.0

问题

How can I format the below XML date element in XSLT version1.0 ? The GenerationTime has to be formatted in pattern yyyy-MM-dd'T'HH:mm:ss in the output XML with the date value in UTC.

xslt processer used is xalan

<Values>
  <value name="cardGenerated">yes</value> 
  <value name="GenerationTime">Tue Dec 29 14:32:53 EST 2020</value>
<Values>

the output would look like

 <Values>
  <value name="cardGenerated">yes</value> 
  <value name="GenerationTime">2020-12-19T19:32:53Z</value>
<Values>

来源：https://stackoverflow.com/questions/65518537/converting-date-from-a-timezone-to-utc-xslt-1-0