code: def log_url (self, url_data):
          
          node = self.get_node(url_data)
          if node is not None:
              self.writeln(u'  "%s" [' % dotquote(node["label"]))
              if self.has_part("realurl"):
                  self.writeln(u'    href="%s",' % dotquote(node["url"]))
              if node["dltime"] >= 0 and self.has_part("dltime"):
                  self.writeln(u"    dltime=%d," % node["dltime"])
              if node["size"] >= 0 and self.has_part("dlsize"):
                  self.writeln(u"    size=%d," % node["size"])
              if node["checktime"] and self.has_part("checktime"):
                  self.writeln(u"    checktime=%d," % node["checktime"])
              if self.has_part("extern"):
                  self.writeln(u"    extern=%d," % node["extern"])
              self.writeln(u"  ];")
docs: Write one node.