code: func Wait(durations ...time.Duration) Strategy {
  	return func(attempt uint) bool {
  		if 0 < attempt && 0 < len(durations) {
  			durationIndex := int(attempt - 1)
  
  			if len(durations) <= durationIndex {
  				durationIndex = len(durations) - 1
  			}
  
  			time.Sleep(durations[durationIndex])
  		}
  
  		return true
  	}
  }
docs: // Wait creates a Strategy that waits the given durations for each attempt after
  // the first. If the number of attempts is greater than the number of durations
  // provided, then the strategy uses the last duration provided.