test the basic encypt method

string_test.py

def string_process(string, encrypt):
    int_list = []
    for s in string:
        int_list.append(ord(s))

    result = ''
    for i in int_list:
        if i >= ord('A') and i <= ord('z'):
            if encrypt:
                result += chr(i - 3)
            else:
                result += chr(i + 3)
        else:
            result += chr(i)
    return result


def encrypt(string):
    result = string_process(string, True)
    return result


def decrypt(string):
    result = string_process(string, False)
    return result


if __name__ == '__main__':
    string = "Ghost in the shell!"
    encrypt_string = encrypt(string)
    print encrypt_string
    decrypt_string = decrypt(encrypt_string)
    print decrypt_string