Nayuta Transparency Fixer v3

import os
import sys

def get_data(filename):
    totalbytes = os.path.getsize(filename)
    infile = open(filename, 'rb')
    totalfiledata = infile.read(totalbytes)
    infile.close()
    return totalfiledata

def myprogram(filename):
    filedata = get_data(filename + '.orig')
    pos = 0x36
    transparent_color = -1
    transparency_bytes = []
    for x in range(256):
        transparency_byte = filedata[pos + x*4 + 3]
        transparency_bytes.append(transparency_byte)
        if transparency_byte == '\x00':
            if transparent_color != -1:
                print 'More than one transparent color.'
                print 'First transparent color was %s.' % hex(transparent_color)
                print 'Second transparent color was %s.' % hex(x)
                quit()
            transparent_color = x
    print 'Transparent color is %s: %s.' % \
          (hex(transparent_color), \
           filedata[0x36 + transparent_color*4:\
                    0x36 + (transparent_color + 1)*4].encode('hex'))
    transparent_color = filedata[0x36 + transparent_color*4:\
                                 0x36 + transparent_color*4 + 3]

    filedata = get_data(filename + '.bmp')
    pos = 0x36
    colortable = []
    transparent_color_flag = False
    for x in range(256):
        color = filedata[pos + x*4:pos + x*4 + 3]
        if color == transparent_color:
            if transparent_color_flag == True:
                print 'Multiple transparent colors.'
                quit()
            transparent_color_flag = True
            colortable.append(color + '\x00')
        else:
            colortable.append(color + '\xff')

    if not transparent_color_flag:
        print 'No transparent color.'
        quit()

    outfile = open(filename + '.bmp','wb')
    outfile.write(filedata[:0x36] + "".join(colortable) + filedata[0x436:])
    outfile.close()
    print 'Updated %s.' % (filename + '.bmp')
sys.argv.append('title01')
myprogram(sys.argv[1])