docs: def format(self, node_formatter=None, separator='/'):
          # type: (Optional[Callable[[PathParam], str]]) -> str
          """
          Format a URL path.
          
          An optional `node_parser(PathNode)` can be supplied for converting a 
          `PathNode` into a string to support the current web framework.  
          
          """
          if self._nodes == ('',):
              return separator
          else:
              node_formatter = node_formatter or self.odinweb_node_formatter
              return separator.join(node_formatter(n) if isinstance(n, PathParam) else n for n in self._nodes)