如何在terraform中比较变量并选择正确的键、值对

variable "environment" {
  description = "The environment to deploy"
  type        = string
  default     = "dev"
  validation {
    condition     = contains(["dev", "prod"], var.environment)
    error_message = "Invalid environment"
  }
}

variable "region" {
  description = "The region to deploy"
  type        = string
  default     = "us-west-1"
  validation {
    condition     = contains(["us-west-1", "us-east-1"], var.region)
    error_message = "Invalid region"
  }
}

locals {
  environment_vars = {
    dev = {
      key1 = "value1-dev"
      key2 = "value2-dev"
    }
    prod = {
      key1 = "value1-prod"
      key2 = "value2-prod"
    }
  }

  region_vars = {
    us-west-1 = {
      key3 = "value3-west"
      key4 = "value4-west"
    }
    us-east-1 = {
      key3 = "value3-east"
      key4 = "value4-east"
    }
  }
}

resource "example_resource" "example" {
  key1 = local.environment_vars[var.environment].key1
  key2 = local.environment_vars[var.environment].key2
  key3 = local.region_vars[var.region].key3
  key4 = local.region_vars[var.region].key4
}