NAND Flash reader using FTDI
The code you are using, specifically FlashDevice.py attempts to match a variety of manufacturer IDs.  

    if id[0]==0x98:
        self.Manufacturer="Toshiba";
    if id[0]==0xec:
        self.Manufacturer="Samsung";
    if id[0]==0x04:
        self.Manufacturer="Fujitsu";
    if id[0]==0x8f:
        self.Manufacturer="National Semiconductors";
    if id[0]==0x07:
        self.Manufacturer="Renesas";
    if id[0]==0x20:
        self.Manufacturer="ST Micro";
    if id[0]==0xad:
        self.Manufacturer="Hynix";
    if id[0]==0x2c:
        self.Manufacturer="Micron";
    if id[0]==0x01:
        self.Manufacturer="AMD";
    if id[0]==0xc2:
        self.Manufacturer="Macronix";


Likely yours is not being matched either because it is misread, or unknown, and this leaves the field undefined, causing the error you see.  I would suggest you try preceding these "if" statement with a default, ie:

    self.Manufacturer="Unrecognized";
    if id[0]==0x98:
        self.Manufacturer="Toshiba";


Going a step further you could try something like this (completely untested):

    self.Manufacturer=hex(id[0])+" is unrecognized";
    if id[0]==0x98:
        self.Manufacturer="Toshiba";


According to your data sheet, the code for your chip should be 0xad which is in the list, so likely these changes won't actually get things working, but will get you past that particular program crash and so perhaps allow you to learn more.