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#WILL `CORRUPT` A BMP

import struct

string = "SECRET MESSAGE"

stdin = open("YourBMPhere.bmp","r")

x = stdin.read()

stdin.close()

offset = struct.unpack("<I",x[10:14])[0]

x,y = x[:offset],x[offset:]

z = ''

for char in y:
    z+=(chr(ord(char)^2))

new_offset = offset+len(string)

x = x+struct.pack("<I",new_offset)+string+z

stdout = open("result.bmp","w+")

stdout.write(x)

stdout.close()