docs: def parse_bytes(self, i):
          """Parse byte."""
  
          value = int(self.get_byte(i), 16)
          single = self.get_single_stack()
          if self.span_stack:
              text = self.convert_case(chr(value), self.span_stack[-1])
              value = ord(self.convert_case(text, single)) if single is not None else ord(text)
          elif single:
              value = ord(self.convert_case(chr(value), single))
          if self.use_format and value in _CURLY_BRACKETS_ORD:
              self.handle_format(chr(value), i)
          else:
              self.result.append('\\%03o' % value)