Answer: Secret Code #154

The secret message says:

I CAN CODE

The shift was 11.

Letter by letter

Secret letter	L	N	O	P	T	Y	Z
Real letter	A	C	D	E	I	N	O

Decode it with Python

This program does the decoding for you. Change the secret and the shift to crack other messages!

secret = "T NLY NZOP"
shift = 11
message = ""

for letter in secret:
    if letter.isalpha():
        number = (ord(letter) - ord("A") - shift) % 26
        message = message + chr(number + ord("A"))
    else:
        message = message + letter

print(message)

When you run it, it prints:

I CAN CODE