code: def tostring(self, encoding):
          
          if self.kind == 'string':
              if encoding is not None:
                  return self.converted
              return '"{converted}"'.format(converted=self.converted)
          elif self.kind == 'float':
              # python 2 str(float) is not always
              # round-trippable so use repr()
              return repr(self.converted)
          return self.converted
docs: quote the string if not encoded
              else encode and return