How to Get Self Id of a datadog monitor?

Terraform HCP Terraform
1

I would like to have a hyperlink to this monitor on PagerDuty.
I have tried to do in this way, but it does not work. The system told me that there’s a cycle.

Shortcut: https://app.datadoghq.com/monitors/${datadog_monitor.monitor_1234[each.key].id}

resource "datadog_monitor" "monitor_1234" {
  for_each = {
    for entry in local.dcs_list: "${entry.wave}_${entry.dc}" => entry
  }

  name = "[${each.value.dc} | ${each.value.wave}] monitor_name"
  priority = 1
  type = "query alert"
  query = "a valid query."
  message = <<-EOT
    Shortcut: https://app.datadoghq.com/monitors/<This_Monitor_id?>
  EOT

  notify_audit = false
  locked = true
  timeout_h = 0
  include_tags = true
  no_data_timeframe = 140
  require_full_window = false
  new_host_delay = 300
  notify_no_data = true
  renotify_interval = 0
  escalation_message = ""
  monitor_thresholds {
    critical = 0
  }
}