docs: def mount(self, prefix, app, **options):
          """ Mount an application (:class:`Bottle` or plain WSGI) to a specific
              URL prefix. Example::
  
                  parent_app.mount('/prefix/', child_app)
  
              :param prefix: path prefix or `mount-point`.
              :param app: an instance of :class:`Bottle` or a WSGI application.
  
              Plugins from the parent application are not applied to the routes
              of the mounted child application. If you need plugins in the child
              application, install them separately.
  
              While it is possible to use path wildcards within the prefix path
              (:class:`Bottle` childs only), it is highly discouraged.
  
              The prefix path must end with a slash. If you want to access the
              root of the child application via `/prefix` in addition to
              `/prefix/`, consider adding a route with a 307 redirect to the
              parent application.
          """
  
          if not prefix.startswith('/'):
              raise ValueError("Prefix must start with '/'")
  
          if isinstance(app, Bottle):
              return self._mount_app(prefix, app, **options)
          else:
              return self._mount_wsgi(prefix, app, **options)