code: def add_handlers(self, host_pattern: str, host_handlers: _RuleList) -> None:
          
          host_matcher = HostMatches(host_pattern)
          rule = Rule(host_matcher, _ApplicationRouter(self, host_handlers))
  
          self.default_router.rules.insert(-1, rule)
  
          if self.default_host is not None:
              self.wildcard_router.add_rules(
                  [(DefaultHostMatches(self, host_matcher.host_pattern), host_handlers)]
              )
docs: Appends the given handlers to our handler list.
  
          Host patterns are processed sequentially in the order they were
          added. All matching patterns will be considered.