How to fetch current user name used to connect to aws?

all aws resources created should have a predefined set o tags.

i couldnt find how to get who created the resource (username? arn?)

standard_tags = {
  Environment = "{{ env `BUILD_ENVIRONMENT` }}"
  CreatedDate = "{{ isotime `2006-01-02 03:04:05 -03:00` }}"
  CreatedBy   = "{{ ??? }}"
}