How to format {{datetime}} as 'YYYY-MM-DD HH: mm: ss'？

[PiccoloYu]

{
"jsdocs_extra_tags" : [
"@author author ",
"@datetime {{datetime}}",//YYYY-MM-DD HH:mm:ss
],
"jsdocs_extra_tags_go_after" : false,
"jsdocs_function_description":true
}