https://community.lego.com/t5/LEGO-VIDEO-GAMES/SOPO-Society-Of-the-Protection-of-Orcs-Video-Games-Edition/m-p/8338878/highlight/true#M188931

SOPO.py

class SOPOMessages:

    def __init__(self):
        self.__encodeLegend = {}
        self.__decodeLegend = {}

        # Only decode the legends once per instance
        # We only need to check if the encoding legend is generated
        # for both legends are generated at the same time
        if len(self.__encodeLegend) == 0:
            self.__makeLegends()

    def __makeLegends(self):
        key = "A=G B=L C=Q D=V E=A F=D G=H H=M I=R J=W K=B L=E M=I N=S O=N P=X Q=C R=F S=J T=O U=T V=Y W=K X=P Y=Z Z=U".lower().split(" ")

        # Generate the legend
        for i in key:
            code = i.split("=")
            self.__encodeLegend[code[0]] = code[1]
            self.__decodeLegend[code[1]] = code[0]

    def __preserveCase(self, char, newChar):
        if char.isupper():
            return newChar.upper()
        return newChar

    def decodeMessage(self, msg):
        decoded = []

        for char in msg:
            lowerChar = char.lower()

            # This is not a defined key
            if lowerChar not in self.__decodeLegend.keys():
                decoded.append(char)

            # This is a defined key
            else:
                secretChar = self.__decodeLegend[lowerChar]
                decoded.append(self.__preserveCase(char, secretChar))
        return "".join(decoded)

    def encodeMessage(self, msg):
        encoded = []

        for char in msg:
            lowerChar = char.lower()

            # This is not a defined key
            if lowerChar not in self.__encodeLegend.keys():
                encoded.append(char)

            # This is a defined key
            else:
                secretChar = self.__encodeLegend[lowerChar]
                encoded.append(self.__preserveCase(char, secretChar))
        return "".join(encoded)


reader = SOPOMessages()
decoded = reader.decodeMessage("OMAFA ZG HN!!!")
print(decoded)

encoded = reader.encodeMessage("Oh really now?")
print(encoded)