code: func Reset() {
  	hm.Lock()
  	defer hm.Unlock()
  
  	gm.Lock()
  	defer gm.Unlock()
  
  	cm.Lock()
  	defer cm.Unlock()
  
  	counters = make(map[string]uint64)
  	counterFuncs = make(map[string]func() uint64)
  	gauges = make(map[string]func() int64)
  	histograms = make(map[string]*Histogram)
  	inits = make(map[interface{}]func())
  }
docs: // Reset removes all existing counters and gauges.