class_docstr: Matches requests from host that is equal to application's default_host.
  Always returns no match if ``X-Real-Ip`` header is present.
class_docstr_tok: ["Matches","requests","from","host","that","is","equal","to","application","'s","default_host",".","Always","returns","no","match","if","``","X-Real-Ip","``","header","is","present","."]
code: def match(self, request):
      # Look for default host if not behind load balancer (for debugging)
      if "X-Real-Ip" not in request.headers:
          if self.host_pattern.match(self.application.default_host):
              return {}
      return None
  
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 2 for calling the DefaultHostMatches obj's underlying member method code with example usage: obj.match(request) and returns: None, dict