docs: def reverse(self, *args, **kwargs):
          """Look up a path by name and fill in the provided parameters.
  
          Example:
  
              >>> handler = lambda: None  # just a bogus handler
              >>> router = PathRouter(('post', '/posts/{slug}', handler))
              >>> router.reverse('post', slug='my-post')
              '/posts/my-post'
          """
          (name,) = args
          return self._templates[name].fill(**kwargs)