code: def start_tag(self, alt=None, empty=False):
          
          if alt:
              name = alt
          else:
              name = self.name
          result = "<" + name
          for it in self.attr:
              result += ' %s="%s"' % (it, escape(self.attr[it], {'"':"&quot;", '%': "%%"}))
          if empty:
              return result + "/>%s"
          else:
              return result + ">"
docs: Return XML start tag for the receiver.