Example Lookup Module

main.tf

variable "vpc_id" {
  description = "VPC ID to create the subnet in"
}

# Just setup multiple of these as needed
variable "sec_internal_admin" {
  description = "The security group ID for the internal admin group"
  default {
    vpc-blahblah = "sg-deadbeef"
    vpc-etcetcet = "sg-00000001"
  }
}

# Just setup multiple of these as needed
output "sec_internal_admin_id" {
  value = "${lookup(var.sec_internal_admin, var.vpc_id)}"
}