code: def nameify(self, camelsplit=False, ascii=True, sep='-'):
          
          s = String(str(self))  # immutable
          if camelsplit == True:
              s = s.camelsplit()
          s = s.hyphenify(ascii=ascii).replace('-', sep)
          if len(s) == 0 or re.match("[A-Za-z_]", s[0]) is None:
              s = "_" + s
          return String(s)
docs: return an XML name (hyphen-separated by default, initial underscore if non-letter)