code: def read_filtering_config (self):
          
          section = "filtering"
          if self.has_option(section, "ignorewarnings"):
              self.config['ignorewarnings'] = [f.strip().lower() for f in \
                   self.get(section, 'ignorewarnings').split(',')]
          if self.has_option(section, "ignore"):
              for line in read_multiline(self.get(section, "ignore")):
                  pat = get_link_pat(line, strict=1)
                  self.config["externlinks"].append(pat)
          if self.has_option(section, "nofollow"):
              for line in read_multiline(self.get(section, "nofollow")):
                  pat = get_link_pat(line, strict=0)
                  self.config["externlinks"].append(pat)
          if self.has_option(section, "internlinks"):
              pat = get_link_pat(self.get(section, "internlinks"))
              self.config["internlinks"].append(pat)
          self.read_boolean_option(section, "checkextern")
docs: Read configuration options in section "filtering".