code: def output_exists(config, props, service, log_message=True):
      """Determine if this service and destination combo has already been created
  
      Args:
          config (dict): The outputs config that has been read from disk
          props (OrderedDict): Contains various OutputProperty items
          service (str): The service for which the user is adding a configuration
          log_message (bool): Optionally log the error message
  
      Returns:
          [boolean] True if the service/destination exists already
      """
      if (
          service in config
          and props["descriptor"].value in config[service]
      ):
          if log_message:
              LOGGER.error(
                  "This descriptor %s is already configured for %s. "
                  "Please select a new and unique descriptor",
                  props["descriptor"].value,
                  service,
              )
          return True
  
      return False
  
label_desc: Use image node_id 1 for calling a global function with example usage: output_exists(config, props, service, log_message) and returns: False, True