code: def __init__(self, server):
      super().__init__(server)
      self.subsystem = "semaphore"
  
imports: from __future__ import annotations
  from prometheus_client.core import CounterMetricFamily, GaugeMetricFamily
  from distributed.http.prometheus import PrometheusCollector
label_desc: Use image node_id 1 to create a new SemaphoreMetricCollector object from inherited base classes: PrometheusCollector with example: obj = SemaphoreMetricCollector(server)