17.py

fname = "secret.txt"

with open(fname, "r", encoding="utf-8") as file:
    for line in file:
        string = line.rstrip("\n")
        res = ''

        for char in string:
            b = bin(ord(char))[2:]
            if len(b) % 8 != 0:
                bytenum = len(b) // 8 + 1
                b = "0" * (8 * bytenum - len(b)) + b
            if len(b) <= 8:
                res += chr(int(b, 2))
            else:
                res += chr(int(b[8:], 2))

        print(res)