docs: def start(self):
          """Start the process with daemonization.
  
          If the process is already started this call should exit with code
          ALREADY_RUNNING. Otherwise it must call the 'daemonize' method and then
          call 'run'.
          """
          if self.pid is not None:
  
              LOG.error(
                  "The process is already running with pid {0}.".format(self.pid)
              )
              sys.exit(exit.ALREADY_RUNNING)
  
          self.daemonize()
  
          LOG.info("Beginning run loop for process.")
          try:
  
              self.run()
  
          except Exception:
  
              LOG.exception("Uncaught exception in the daemon run() method.")
              self.stop()
              sys.exit(exit.RUN_FAILURE)