code: public static function read(string $key = 'default', $format = self::FORMAT_MILLISECONDS) {
      if (isset(self::$timers[$key])) {
        return self::formatTime(self::$timers[$key]->read(), $format);
      }
      throw new \LogicException('Reading timer when the given key timer was not initialized.');
    }
docs: Returns the time elapsed in the format requested in the $format parameter.
  To access a specific timer, pass the same key that
  @see \Ayesh\PHP_Timer\Timer::start() was called with. If the timer was not
  started, a \LogicException will be thrown.
  
  The default format is milliseconds. See the class constants for additional
  formats.
  
  @param string $key The key that the timer was started with. Default value is
  "default" throughout the class.
  @param string $format
  @return mixed The formatted time.
  @throws \LogicException