LF2 WAV Renaming Tool

import os, sys
from random import randint
import ctypes

def decrypt_lf2(edata):
    key="odBearBecauseHeIsVeryGoodSiuHungIsAGo";pos=0;ddata=''
    for a in range(123, len(edata)-1):
        try:
            ddata+=chr(ord(edata[a])-ord(key[pos]))
        except ValueError:
            pass
        pos+=1
        if pos==len(key):
            pos=0
    return ddata

def encrypt_lf2(ddata):
    key="odBearBecauseHeIsVeryGoodSiuHungIsAGo"
    pos=0
    edata=''
    for a in range(0, len(ddata)-1):
        edata+=chr(ord(ddata[a])+ord(key[pos]))
        pos+=1
        if pos==len(key):
            pos=0
    return (" "*123)+edata

ctypes.windll.kernel32.SetConsoleTitleA("A-WAV Name Surgeon")
fns=[]

if "data" not in os.listdir(os.getcwd()):
    os.system("color 0C")
    raw_input("#Place this next to your LF2 exe. Could not locate the \'data\' folder!")
else:
    os.system("color 0A")
    for a in os.listdir(os.getcwd()+"\\data"):
        if a.endswith(".dat"): fns.append("data\\"+a)


    x=lambda y: decrypt_lf2(open(y).read())

    mode = None
    while mode == None:
        a = raw_input("Enter 0 to have me generate new names for you. \nEnter 1 if you'd like to set new names yourself. >> ")
        if a in ["1", "0"]:
            mode = int(a)
            break

    sound_files = {}
    for datfile in fns:
        dft = x(datfile)
        last_pos = dft.find("sound:")
        print "###Currently operating on: " + datfile
        while last_pos != -1:
            wavname = dft[dft.find("sound:", last_pos+1)+6:dft.find("\n", dft.find("sound:", last_pos+1)+10)]
            wavname = wavname.rstrip(" ")
            wavname = wavname.rstrip("\"")
            wavname = wavname.lstrip(" ")
            wavname = wavname.lstrip("\"")
            loc = wavname[:wavname.rfind("\\") + 1]
            name = wavname[wavname.rfind("\\") + 1:]
            if len(wavname) > 20:
                print "#Checking " + wavname
                if wavname in sound_files.keys():
                    new_name = sound_files[wavname]
                else:
                    if mode == 0:
                        while True:
                            new_name = ["abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOPQRSTUVWXYZ"][randint(0,1)][randint(0,25)]+str(randint(0,9))+".wav"
                            if loc+new_name not in sound_files.keys():
                                break;
                    else:
                        new_name = raw_input(name + " name is too long. \nEnter a shorter name>> ")
                        while True:
                            if len(new_name + loc) > 20 and loc+new_name not in sound_files.keys():
                                break
                            elif len(new_name + loc) > 20:
                                new_name = raw_input("Name is still too long. Please write another>> ")
                            else:
                                new_name = raw_input("Name conflict. Please write another>> ")
                    try:
                        os.rename(wavname, loc+new_name)
                    except WindowsError:
                        print "Warning: File " + wavname + " could not be located"
                    sound_files[wavname] = new_name
                while dft.find(wavname) != -1:
                    dft = dft.replace(wavname, loc+new_name)
                new_dft = encrypt_lf2(dft)

                #write to new data
                datfile_obj = open(datfile, "w")
                datfile_obj.write(new_dft)
                datfile_obj.close()
            last_pos = dft.find("sound:", last_pos+1)
    raw_input("\n----All is done and ready!----")