Automate setting Fix versions field to the value of year.workweek when an issue is closed

[Tom Horton]

I'd like to use the new Project Automation feature to set the Fix versions field for an issue to a value like 2020.14 when the issue is closed.

The value is a calculation for the current year & "." & current work work week

Is this possible? Is current year and current work week a function I can use in Jira or Jira Service Desk?