class_docstr: Rule-based router implementation.
class_docstr_tok: ["Rule-based","router","implementation","."]
docstr: Override this method for additional preprocessing of each rule.
  
  :arg Rule rule: a rule to be processed.
  :returns: the same or modified Rule instance.
docstr_tok: ["Override","this","method","for","additional","preprocessing","of","each","rule",".",":","arg","Rule","rule",":","a","rule","to","be","processed",".",":","returns",":","the","same","or","modified","Rule","instance","."]
code: def process_rule(self, rule):
      """Override this method for additional preprocessing of each rule.
  
      :arg Rule rule: a rule to be processed.
      :returns: the same or modified Rule instance.
      """
      return rule
  
imports: from __future__ import absolute_import, division, print_function
  import re
  from functools import partial
  from tornado import httputil
  from tornado.httpserver import _CallableAdapter
  from tornado.escape import url_escape, url_unescape, utf8
  from tornado.log import app_log
  from tornado.util import basestring_type, import_object, re_unescape, unicode_type
label_desc: Use image node_id 3 for calling the RuleRouter obj's underlying member method code with example usage: obj.process_rule(rule) and returns: rule