Setting password once does not retain between sessions

[nus-pe-script]

Describe the bug
I need top keep resetting the password in order for the system to work. I.I if I set a password once the next time I save there is no password on the file

To Reproduce
Steps to reproduce the behavior:

1. password Set on the file
2. Close app
3. Edit the file
4. Close app
5. AB is unencrypted

Expected behavior
The password should be retained between uses.

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Reported by: @arjo129
Severity: Low

_{[original: nusCS2113-AY1819S1/pe-1#603]}