## Get ISO 8601 week number - Get-Date -UFormat %$V or %W are not reliable or flexible
## From Insomniac at https://stackoverflow.com/questions/46691143/get-the-iso-8601-week-of-year-of-a-given-date-in-powershell

(Get-Culture).Calendar.GetWeekOfYear( (Get-Date) ,[ System.Globalization.CalendarWeekRule]::FirstFourDayWeek , [DayOfWeek]::Monday )