External Data Source and Data Source: aws_ami Error

I am using Terraform to obtain a specific AMI that's created weekly to update EC2 instances. The AMI ID is unknown, however I'm able to retrieve the AMI by name. I'm using Terraform AWS External Data Source, Data Source and a bash script to achieve this. However, I'm receiving the error below. I also provided the bash script and Terraform config file below;

Please advise how to covert to a string or if there is a better way to do this.

Thanks

Michael

Blockquote│ Error: Incorrect attribute value type │ │ on main.tf line 20, in data "aws_ami" "get_ami_id": │ 20: values = "{$data.external.get_ami_name.results}" │ │ Inappropriate value for attribute "values": list of string required.

` get_ami_name.sh #!/bin/bash

AMI_NAME=$(aws ec2 describe-images --owners 5555566666 --query 'Images[?Name>=`em`][]'|grep Name|grep -v DeviceName|sort -n|tail -5|sort -t- -nrk5,5|awk '{print $2}'|sed 's/"//g')
jq -n --arg ami_name "$AMI_NAME" '{"ami_name":$ami_name}'
#
# Terraform Main.tf
  #
# Get lastest AMI NAME
#
data "external" "get_ami_name" {
   program = ["bash", "${path.root}/get_ami_name.sh"]
}

output "ami_name_out" {
   value = ["data.external.get_ami_name.results"]
}

#
# Get AMI ID based on name retrived
#
data "aws_ami" "get_ami_id" {
   most_recent = true
   owners = ["555556666"]
   filter {
      name = "name"
          values = "{$data.external.get_ami_name.results}"
   }
}