def METHOD_NAME(self, cipher: str):
    plain = ""
    lower_fixer = "tonquerzlawicvfjpsyhgdmkbx"
    upper_fixer = "JKABRUDQZCTHFVLIWNEYPSXGOM"
    for ch in cipher.strip():
        if ch.islower():
            plain += lower_fixer[ord(ch) - ord("a")]
        elif ch.isupper():
            plain += upper_fixer[ord(ch) - ord("A")]
        else:
            plain += ch
    return plain