Wrap code inside bv.begin_undo_actions() and bv.commit_undo_actions().
Architecture['x86'].get_instruction_text(bv.read(here, 2), 0)t = transform.Transform['XOR']
t.encode(bv.read(0, bv.end), {'key': 'secret_key'})string = ''
for i in bv.get_ascii_string_at(here).value:
string += chr(ord(i) ^ 0x3f)
print(string)