code: def encode(in_bytes):
      
      final_zero = True
      out_bytes = []
      idx = 0
      search_start_idx = 0
      for in_char in in_bytes:
          if in_char == '\x00':
              final_zero = True
              out_bytes.append(chr(idx - search_start_idx + 1))
              out_bytes.append(in_bytes[search_start_idx:idx])
              search_start_idx = idx + 1
          else:
              if idx - search_start_idx == 0xFD:
                  final_zero = False
                  out_bytes.append('\xFF')
                  out_bytes.append(in_bytes[search_start_idx:idx+1])
                  search_start_idx = idx + 1
          idx += 1
      if idx != search_start_idx or final_zero:
          out_bytes.append(chr(idx - search_start_idx + 1))
          out_bytes.append(in_bytes[search_start_idx:idx])
      return ''.join(out_bytes)
docs: Encode a string using Consistent Overhead Byte Stuffing (COBS).
      
      Input is any byte string. Output is also a byte string.
      
      Encoding guarantees no zero bytes in the output. The output
      string will be expanded slightly, by a predictable amount.
      
      An empty string is encoded to '\\x01