docs: def create_app(metadata, processors=None, pipes=None):
      """Return an application instance with processors & pipes setup."""
  
      instance = Application(metadata)
  
      # In order to avoid code duplication, we use existing built-in import
      # processor to import and register built-in processors on the application
      # instance. This is, to be honest, the main purpose of this factory
      # function, because otherwise one must create an Application instance
      # directly.
      import_processors.process(instance, [], imports=[
          "archive = holocron.processors.archive:process",
          "commonmark = holocron.processors.commonmark:process",
          "feed = holocron.processors.feed:process",
          "frontmatter = holocron.processors.frontmatter:process",
          "import-processors = holocron.processors.import_processors:process",
          "jinja2 = holocron.processors.jinja2:process",
          "markdown = holocron.processors.markdown:process",
          "metadata = holocron.processors.metadata:process",
          "pipe = holocron.processors.pipe:process",
          "prettyuri = holocron.processors.prettyuri:process",
          "restructuredtext = holocron.processors.restructuredtext:process",
          "save = holocron.processors.save:process",
          "sitemap = holocron.processors.sitemap:process",
          "source = holocron.processors.source:process",
          "todatetime = holocron.processors.todatetime:process",
          "when = holocron.processors.when:process",
      ])
  
      for name, processor in (processors or {}).items():
          instance.add_processor(name, processor)
  
      for name, pipeline in (pipes or {}).items():
          instance.add_pipe(name, pipeline)
  
      return instance